Battery module, battery pack and vehicle comprising the same

Abstract

A battery module according to an embodiment of the present disclosure includes: a submodule, the submodule including a battery cell stack assembly, a front busbar frame assembly, and a rear busbar frame assembly, the battery cell stack assembly including a plurality of battery cells and heat sinks located between adjacent battery cells, the front busbar frame assembly being coupled to one side of the battery cell stack assembly in the longitudinal direction, and the rear busbar frame assembly being coupled to the other side of the battery cell stack assembly in the longitudinal direction; a module housing, the submodule being housed in the module housing; a front sealing plate, the front sealing plate covering an opening formed on one side of the module housing in the longitudinal direction and including an insulating oil outlet; and a rear sealing plate, the rear sealing plate covering an opening formed on the other side of the module housing in the longitudinal direction and including an insulating oil outlet.

Description

Technical Field

[0001] This disclosure relates to a battery module having a cooling structure using insulating oil, and to a battery pack and vehicle including the battery module. More specifically, it relates to a battery module having a structure in which insulating oil introduced into the module housing flows through the space between the edge of the battery cell and the module housing to cool the battery cell, and to a battery pack and vehicle including the battery module.

[0002] This application claims priority to Korean Patent Application No. 10-2020-0153016, filed in Korea on November 16, 2020, the disclosure of which is incorporated herein by reference. Background Technology

[0003] In battery modules employing indirect water cooling, the cooling performance is limited because the cooling water does not directly contact the individual battery cells but rather indirectly through the module casing containing them. Furthermore, the increased size of the battery module inevitably leads to a loss in energy density because cooling devices, such as separate heat sinks, must be installed externally to create cooling channels.

[0004] To address the issues of indirect water cooling methods, a battery module with the following cooling structure needs to be developed, wherein the insulating oil used for cooling can be directly introduced into the module housing and can directly contact the individual battery cells.

[0005] In the case of battery modules with direct cooling structures that use insulating oil, it is important to ensure the fluid channel structure for efficient cooling and to maintain airtightness so that the insulating oil does not leak to the outside of the module housing and end plates. Summary of the Invention

[0006] Technical issues

[0007] This disclosure aims to address the problems of the related technology, and therefore aims to ensure a smooth path for the insulating oil introduced into the module housing to move smoothly through the busbar frame assembly to the battery cell stack assembly and to flow smoothly in the longitudinal direction of the battery module.

[0008] However, the technical objectives to be addressed by this disclosure are not limited to those described above, and those skilled in the art will clearly understand from the following disclosure that other objectives not mentioned herein will be achieved.

[0009] Technical solution

[0010] In one aspect of this disclosure, a battery module is provided, comprising: a submodule including a battery cell stack assembly, a front busbar frame assembly, and a rear busbar frame assembly, the battery cell stack assembly including a plurality of battery cells and heat sinks located between adjacent battery cells, the front busbar frame assembly being coupled to one side of the battery cell stack assembly in the longitudinal direction, and the rear busbar frame assembly being coupled to the other side of the battery cell stack assembly in the longitudinal direction; a module housing in which the submodule is housed; a front sealing plate covering an opening formed on one side of the module housing in the longitudinal direction and including an insulating oil inlet; and a rear sealing plate covering an opening formed on the other side of the module housing in the longitudinal direction and including an insulating oil outlet.

[0011] The heat sink may include: a main body contact portion located between adjacent battery cells; and an edge cover portion that is bent at either the upper or lower end of the main body contact portion to cover the edge of the battery cell.

[0012] The front busbar frame assembly and the rear busbar frame assembly may include a plurality of insulating oil holes formed at positions corresponding to insulating oil channels formed between the edge of the module housing and the edge of the battery cell and between the edge cover and the edge of the battery cell.

[0013] Insulating oil introduced into the module housing through the insulating oil inlet can pass through the insulating oil hole formed in the front busbar frame assembly and can be introduced into the insulating oil channel.

[0014] Insulating oil passing through the insulating oil channel can pass through the insulating oil holes formed in the rear busbar frame assembly and can be discharged to the outside of the module housing through the insulating oil outlet.

[0015] The front busbar frame assembly and the rear busbar frame assembly may include guide ribs formed at the upper and lower ends, respectively, and extending toward the battery cell stack assembly.

[0016] The heat sink may further include a pair of fixing portions, each having a shape corresponding to a guide rib and formed at two ends in the longitudinal direction of the edge cover, and each of the pair of fixing portions being engaged with the guide rib.

[0017] The battery module may further include a pair of terminal assemblies, each of which includes an external terminal located outside the front sealing plate and a stud passing through the front sealing plate and configured to electrically connect the external terminal to the battery cell.

[0018] The front busbar frame assembly may include: a busbar frame; a plurality of busbars fixed to the busbar frame and connected to the electrode leads of the battery cells; and a pair of internal terminals, each fixed to the busbar frame and connected to the electrode leads of the battery cells located at the outermost position of the battery cells in the battery cell stack assembly.

[0019] The terminal assembly may further include a terminal spacer inserted into a terminal hole formed in the front sealing plate, wherein a stud is secured to an internal terminal and passes through the terminal spacer.

[0020] The terminal assembly may further include a fastening nut that passes through the terminal spacer and the external terminal to a stud and is configured to secure the external terminal tightly to the terminal spacer.

[0021] The terminal assembly may further include a first O-ring that covers the outer peripheral surface of the terminal spacer and is located between the inner surface of the front sealing plate and the internal terminal.

[0022] The stud can be press-fitted through the internal terminal, wherein the terminal assembly further includes a second O-ring located around the stud and between the internal terminal and the busbar frame.

[0023] In another aspect of this disclosure, a battery pack and a vehicle including the battery module are also provided.

[0024] Beneficial effects

[0025] According to one aspect of this disclosure, the insulating oil introduced into the module housing can pass through the busbar frame assembly, move smoothly towards the battery cell stack assembly, and flow smoothly longitudinally within the battery module of the module housing. Additionally, according to one aspect of this disclosure, leakage of the insulating oil flowing inside the module housing can be effectively prevented. Attached Figure Description

[0026] The accompanying drawings illustrate preferred embodiments of the present disclosure and, together with the foregoing disclosure, are intended to provide a further understanding of the technical features of the present disclosure. Therefore, the present disclosure is not to be construed as limited to the drawings.

[0027] Figure 1 This is a perspective view showing a battery module according to an embodiment of the present disclosure.

[0028] Figure 2 This is an exploded perspective view showing a battery module according to an embodiment of the present disclosure.

[0029] Figure 3 It is along Figure 1 A cross-sectional view taken from line A-A'.

[0030] Figure 4 It is shown in Figure 1 A view of the battery module with the front panel and front sealing plate removed.

[0031] Figure 5 and Figure 6 This is a view showing the flow of insulating oil used for cooling.

[0032] Figure 7 and Figure 8 This is a view showing the connection between the heat sink and the battery cell according to this disclosure.

[0033] Figure 9 This is a perspective view showing a heat sink according to the present disclosure.

[0034] Figure 10 This is a view showing the connection structure between the busbar frame assembly and the heat sink according to the present disclosure.

[0035] Figure 11 and Figure 12 This is a view showing the structure of the terminal assembly according to this disclosure. Detailed Implementation

[0036] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Before description, it should be understood that the terminology used in the specification and appended claims should not be construed as limited to its general or dictionary meaning, but rather should be interpreted according to the meaning and concept corresponding to the technical aspects of the present disclosure, based on the principle that the inventors can appropriately define the terms for best interpretation. Therefore, the descriptions presented herein are merely preferred examples for illustrative purposes and are not intended to limit the scope of the present disclosure. It should be understood that other equivalents and modifications may be made to the present disclosure without departing from its scope.

[0037] Reference Figure 1 and Figure 2 According to embodiments of the present disclosure, a battery module includes a submodule 100, a module housing 200, a front sealing plate 300, a rear sealing plate 400, and a pair of terminal assemblies 700, and may further include a front end plate 500 and a rear end plate 600.

[0038] Reference Figures 2 to 9 Submodule 100 includes a battery cell stack assembly 110, a front busbar frame assembly 120A, and a rear busbar frame assembly 120B.

[0039] The battery cell stack assembly 110 includes a plurality of battery cells 111 and a plurality of heat sinks 112 located between adjacent battery cells 111, and may further include at least one buffer pad 113 located between adjacent battery cells 111. The battery cells 111, heat sinks 112 and buffer pads 113 are stacked vertically in a direction perpendicular to the ground (a surface parallel to the XY plane) to form a battery cell stack assembly 110.

[0040] The battery cell 111 can be a pouch cell comprising a pair of electrode leads 111a extending in opposite directions along the longitudinal direction (parallel to the X-axis).

[0041] Reference Figures 7 to 9 The heat sink 112 includes: a main body contact portion 112a located between adjacent battery cells 111; and an edge covering portion 112b, which is bent at either the upper or lower end of the main body contact portion 112a to cover the edge of the battery cell 111. The edge of the battery cell 111 refers to the two side surfaces of the main body of the battery cell 111 in the width direction, i.e., the height direction of the battery module (parallel to the Z-axis). In addition, the heat sink 112 may further include a pair of fixing portions 112c, which are formed on the two ends of the edge covering portion 112b in the longitudinal direction (parallel to the X-axis).

[0042] The main contact portion 112a is located between the bodies of a pair of adjacent battery cells 111 and directly contacts the bodies of the battery cells 111. The main contact portion 112a is configured to rapidly conduct heat generated from the body of the battery cell 111 (i.e., the area housing the electrode assembly (not shown)) along the width direction of the heat sink 112 (i.e., the height direction of the battery module (parallel to the Z-axis)) to the edge cover portion 112b. In this way, the heat conducted to the edge cover portion 112b is moved along the longitudinal direction (parallel to the X-axis) of the battery module and discharged to the outside of the battery module due to the insulating oil flowing through the insulating oil channel P formed between the edge of the battery cell 111 and the edge cover portion 112b.

[0043] The edge cover 112b can not only form the insulating oil channel P as described above, but also absorb external impacts when the battery cell stack assembly 110 is subjected to external impacts and moves in the vertical direction (parallel to the Z-axis) within the module housing 200.

[0044] The fixing part 112c has a shape corresponding to the shape of the guide rib 121b described below. The fixing part 112c can be combined with the guide rib 121b to guide the fastening between the busbar frame assemblies 120A, 120B and the battery cell stack assembly 110 including the heat sink 112.

[0045] The buffer pad 113 can be located between adjacent battery cells 111 and can absorb volume expansion according to the expansion of the battery cells 111.

[0046] The front busbar frame assembly 120A and the rear busbar frame assembly 120B can be coupled to one side and the other side of the battery cell stack assembly 110 in the longitudinal direction to electrically connect multiple battery cells 111. Except that the front busbar frame assembly 120A includes internal terminals 123 and the rear busbar frame assembly 120B does not, the front busbar frame assembly 120A and the rear busbar frame assembly 120B have substantially the same structure. Therefore, a detailed description of the structure of the rear busbar frame assembly 120B will be omitted, and the structure of the front busbar frame assembly 120A will be described primarily.

[0047] Reference Figures 4 to 10 The front busbar frame assembly 120A includes a busbar frame 121, a plurality of busbars 122, and a pair of internal terminals 123. The busbar frame 121 covers the side of the battery cell stack assembly 110 in the longitudinal direction (parallel to the X-axis).

[0048] The busbar frame 121 includes a plurality of insulating oil holes 121a. The insulating oil holes 121a serve as a path through which insulating oil introduced into the module housing 200 via the inlet P1 located at the front sealing plate 300 can pass through the busbar frame 121 and can be introduced into the battery cell stack assembly 110.

[0049] like Figure 7 and Figure 8 As shown, the insulating oil channel P is formed between the edge of the module housing 200 and the edge of the battery cell 111, and between the edge cover 112b and the edge of the battery cell 111. Therefore, the insulating oil hole 121a is formed at a position corresponding to the insulating oil channel P formed between the edge of the module housing 200 and the edge of the battery cell 111, and between the edge cover 112b of the heat sink 112 and the edge of the battery cell.

[0050] Insulating oil introduced into the cell stack assembly 110 through insulating oil holes 121a formed in the front busbar frame assembly 120A passes through insulating oil channels P in the direction of the arrow (see arrow). Figure 5 and Figure 6The insulating oil moving towards the rear busbar frame assembly 120B is introduced into the rear sealing plate 400 through insulating oil holes 121a formed in the rear busbar frame 120B, and discharged to the outside of the battery module through outlet P2 provided at the rear sealing plate 400. During this process, the insulating oil directly contacts the electrode leads 111a of the battery cell 111 and indirectly contacts the body of the battery cell 111 to cool the battery cell 111.

[0051] Busbar 122 is fixed to busbar frame 121 and is electrically connected to a plurality of battery cells 111 through lead wires 111a formed in busbar frame 121.

[0052] Internal terminals 123 are fixed to busbar frame 121 and are coupled to electrode leads 111a of battery cells 111 located at the outermost position of the battery cells 111 in the battery cell stack assembly 110. Internal terminals 123 located on one side of busbar frame 121 in the longitudinal direction serve as positive high-potential terminals, while internal terminals 123 located on the other side of busbar frame 121 in the longitudinal direction serve as negative high-potential terminals. Internal terminals 123 are electrically connected to external terminals 710 described below (see [link]). Figure 11 and Figure 12 ).

[0053] Reference Figures 5 to 10 The busbar frame 121 of the front busbar frame assembly 120A and the busbar frame 121 of the rear busbar frame assembly 120B include a plurality of guide ribs 121b formed at the upper and lower ends in the longitudinal direction (parallel to the Y-axis). The guide ribs 121b extend toward the battery cell stack assembly 110. The guide ribs 121b are formed at positions corresponding to the fixing portions 112c of the heat sink 112.

[0054] As described above, a fixing portion 112c having a shape corresponding to the guide rib 121b is formed on both ends of the edge cover portion 112b in the longitudinal direction (parallel to the X-axis). The movement of the heat sink 112 in the vertical direction (parallel to the Z-axis) and longitudinal direction (parallel to the X-axis) is restricted by the guide rib 121b and the fixing portion 112c. Therefore, when the current busbar frame assembly 120A and the rear busbar frame assembly 120B are combined with the battery cell stack assembly 110, the joining position can be guided, thereby improving assembly convenience.

[0055] Reference Figures 1 to 6The sub-module 100, comprising a battery cell stack assembly 110, a front busbar frame assembly 120A, and a rear busbar frame assembly 120B, is housed within a module housing 200. The module housing 200 has an opening on one side and another side in its longitudinal direction (parallel to the X-axis).

[0056] Reference Figure 5 , Figure 6 , Figure 11 and Figure 12 The front sealing plate 300 covers an opening formed on one side of the module housing 200 in the longitudinal direction (parallel to the X-axis). The front sealing plate 300 includes an insulating oil inlet P1 through which insulating oil is introduced. To prevent leakage of the insulating oil, a gasket G may be located between the edge surface of the front sealing plate 300 and the inner surface of the module housing 200 (see [reference]). Figure 12 ).

[0057] The front sealing plate 300 includes a pair of terminal holes 300a through which components for electrical connection between the external terminal 710 (described below) and the internal terminal 123 disposed in the front busbar frame assembly 120A can pass. The terminal holes 300a are formed at positions corresponding to the internal terminals 123.

[0058] Reference Figure 6 The rear sealing plate 400 covers the opening formed on the other side of the module housing 200 in the longitudinal direction (parallel to the X-axis) and includes an insulating oil outlet P2 through which insulating oil is discharged. Similar to the front sealing plate 300, to prevent leakage of insulating oil, a gasket G may be located between the edge surface of the rear sealing plate 400 and the inner surface of the module housing 200.

[0059] The front sealing plate 300 and the rear sealing plate 400 can be formed of insulating resin used for electrical insulation.

[0060] Reference Figure 11 and Figure 12 The terminal assembly 700 includes an external terminal 710 located outside the front sealing plate 300 and a stud 720 configured to electrically connect the external terminal 710 to the battery cell 111. The stud 720 is secured to an internal terminal 123. The stud 720 can pass through the internal terminal 123 and can be secured to the internal terminal 123 by means of a press-fit method. The stud 720 secured to the internal terminal 123 extends outward through a terminal hole 300a formed in the front sealing plate 300 and engages with the external terminal 710.

[0061] The terminal assembly 700 may further include a terminal spacer 730 having an annular shape and inserted into a terminal hole 300a formed in the front sealing plate 300. The terminal spacer 730 may be formed of a metallic material. When the terminal spacer 730 is provided, a stud 720 passes through the terminal spacer 730.

[0062] The terminal assembly 700 may further include a fastening nut 740 for securing the external terminal 710 to the stud 720. The fastening nut 740 passes through the terminal spacer 730 and the fastening portion 712 of the external terminal 710 and is fastened to the stud 720 to secure the fastening portion 712 of the external terminal 710 to the terminal spacer 730. Thus, the internal terminal 123 and the external terminal 710 are electrically connected to each other through the terminal spacer 730.

[0063] The terminal assembly 700 may further include a first O-ring 750 that covers the outer peripheral surface of the terminal spacer 730 and is located in the internal space between the inner surface of the front sealing plate 300 and the internal terminal 123. (Refer to...) Figure 11 and Figure 12 The first O-ring 750 prevents insulating oil introduced into the space between the front sealing plate 300 and the busbar frame 121 from leaking to the outside of the front sealing plate 300 through the internal space between the insulating oil hole 300a and the terminal spacer 730.

[0064] Furthermore, the terminal assembly 700 may further include a second O-ring 760 located around the stud 720 press-fitted to the inner terminal 123 and exposed in the space between the inner terminal 123 and the busbar frame 121. The second O-ring 760 is located between the inner terminal 123 and the busbar frame 121. The second O-ring 760 prevents insulating oil introduced into the space between the front seal plate 300 and the busbar frame 121 from leaking to the outside of the front seal plate 300 through the space between the inner terminal 123 and the stud 720 and the space between the inner surface of the terminal spacer 730 and the stud 720.

[0065] Reference Figure 1 , Figure 2 , Figure 5 and Figure 6 The front end plate 500 covers the front sealing plate 300 and is fixed to the module housing 200. The rear end plate 600 covers the rear sealing plate 400 and is fixed to the module housing 200.

[0066] The front end plate 500 includes a terminal exposure portion 500a and an inlet exposure portion 500b. The terminal exposure portion 500a is configured to expose the connection portion 711 of the external terminal 710 to the outside of the front end plate 500, and the inlet exposure portion 500b is configured to expose the insulating oil inlet P1 to the outside of the front end plate 500. The rear end plate 600 includes an outlet exposure portion 600b configured to expose the insulating oil outlet P2 to the outside of the rear end plate 600.

[0067] When the front-end plate 500 and the rear-end plate 600 are applied to the battery module according to the present disclosure, gaskets for preventing leakage of insulating oil may be applied to the joint between the front-end plate 500 and the module housing 200 and the joint between the rear-end plate 600 and the module housing 200.

[0068] The battery pack and vehicle according to embodiments of the present disclosure include the battery module as described above. The battery pack includes at least one battery module and a battery pack housing housing the at least one battery module. The battery module can be fastened to the battery pack housing via fastening holes H formed in the front end plate 500 and / or the rear end plate 600. That is, space is provided for fastening components such as bolts to be inserted for fastening between the battery module and the battery pack housing. When the battery pack according to the present disclosure includes multiple battery modules, the multiple battery modules can be fastened to each other via the fastening holes H formed in the front end plate 500 and / or the rear end plate 600.

[0069] Although embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above. Various modified embodiments of the present disclosure can be made by those skilled in the art without departing from the scope of the present disclosure as claimed in the claims.

Claims

1. A battery module comprising: a sub-module including a battery cell stack assembly including a plurality of battery cells and a heat sink between adjacent battery cells, a front busbar frame assembly combined with one side of the battery cell stack assembly in a longitudinal direction of the battery cell stack assembly, and a rear busbar frame assembly combined with the other side of the battery cell stack assembly in the longitudinal direction of the battery cell stack assembly; a module case in which the sub-module is accommodated; a front sealing plate covering an opening portion formed on one side of the module case in a longitudinal direction of the module case and including an insulating oil inlet; and a rear sealing plate covering an opening portion formed on the other side of the module case in the longitudinal direction of the module case and including an insulating oil outlet, wherein the heat sink includes: a main body contact portion between adjacent battery cells; and an edge cover portion bent at any one of an upper end and a lower end of the main body contact portion to cover an edge of the battery cell, wherein an insulating oil passage is formed between the module case and the edge of the battery cell and between the edge cover portion and the edge of the battery cell, wherein each of the front busbar frame assembly and the rear busbar frame assembly includes a plurality of insulating oil holes.

2. The battery module of claim 1, wherein, The plurality of insulating oil holes are formed at positions corresponding to the insulating oil passage formed between the module case and the edge of the battery cell and between the edge cover portion and the edge of the battery cell.

3. The battery module of claim 2, wherein, Insulating oil introduced into the module case through the insulating oil inlet passes through the insulating oil holes formed in the front busbar frame assembly and is introduced into the insulating oil passage.

4. The battery module of claim 3, wherein, The insulating oil passing through the insulating oil passage passes through the insulating oil holes formed in the rear busbar frame assembly and is discharged to the outside of the module case through the insulating oil outlet.

5. The battery module of claim 1, wherein, The front busbar frame assembly and the rear busbar frame assembly include guide ribs formed at upper and lower ends, respectively, and extending toward the battery cell stack assembly.

6. The battery module of claim 5, wherein, The heat sink further includes a pair of fixing portions each having a shape corresponding to the guide rib and formed on both ends in the longitudinal direction of the edge cover portion, and each combined with the guide rib. 7.The battery module of claim 1, further comprising a pair of terminal assemblies each including an external terminal located outside the front sealing plate, and a stud passing through the front sealing plate and configured to electrically connect the external terminal to the battery cell.

8. The battery module of claim 7, wherein, The front busbar frame assembly includes: a busbar frame; a plurality of busbars fixed to the busbar frame and connected to electrode leads of the battery cells; and a pair of internal terminals each fixed to the busbar frame and connected to electrode leads of a battery cell located at an outermost position among the battery cells disposed in the battery cell stack assembly.

9. The battery module of claim 8, wherein, The terminal assembly further includes a terminal spacer inserted into a terminal hole formed in the front sealing plate, wherein the stud is fixed to the inner terminal and passes through the terminal spacer.

10. The battery module of claim 9, wherein, The terminal assembly further includes a fastening nut fastened to the stud through the terminal spacer and the outer terminal and configured to tightly fix the outer terminal to the terminal spacer.

11. The battery module of claim 10, wherein, The terminal assembly further includes a first O-ring covering an outer circumferential surface of the terminal spacer and located between an inner surface of the front sealing plate and the inner terminal.

12. The battery module of claim 11, wherein, The stud is press-fitted by passing through the inner terminal, wherein the terminal assembly further includes a second O-ring located around the stud and between the inner terminal and the busbar frame.

13. A battery pack including the battery module according to any one of claims 1 to 12.

14. A vehicle including the battery module according to any one of claims 1 to 12.

Images