Battery module

Abstract

A battery module according to one embodiment of the present application includes: a battery cell; a case covering the battery cell, the case including an electrically conductive material; a busbar electrically connected with the battery cell, the busbar including a terminal exposed to an outside of the case; and a barrier disposed between the terminal and the case, in which a groove can be included at an end portion of the barrier.

Description

Technical Field

[0001] This invention relates to a battery module. Background Technology

[0002] With the development and increasing demand for technologies such as mobile devices, electric vehicles, and energy storage systems (ESS), the demand for secondary batteries as an energy source is rapidly increasing. The interconversion between chemical energy and electrical energy in a secondary battery is reversible, therefore, a secondary battery is a battery that can be repeatedly charged and discharged.

[0003] However, ensuring safety is a critical issue due to the risk of explosion when lithium-ion batteries overheat. Overheating in lithium-ion batteries can occur for various reasons, one of which is when an overcurrent exceeding the battery's limits flows through it. When an overcurrent flows, the lithium-ion battery generates heat due to Joule heating, causing the internal temperature to rise rapidly. A battery heated above a predetermined temperature will explode, and the rapidly rising heat can adversely affect adjacent batteries, leading to a chain reaction of explosions known as thermal runaway. Overcurrent can also be caused by sharp metal objects penetrating the lithium-ion battery, the separator between the anode and cathode contracting and breaking the insulation, or abnormal charging circuits or external loads applying a rush current to the battery.

[0004] In the event of thermal runaway, conductive material can become dispersed within the battery pack, which consists of battery modules, and the insulation distance can rapidly decrease when these byproducts accumulate around the high-voltage terminals. In certain battery modules, if the insulation distance between the terminals and surrounding conductive components (e.g., the aluminum housing) is not adequately ensured, the terminals and surrounding conductive components become energized through conductive material discharged from other battery modules, exacerbating thermal runaway. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] The purpose of this disclosure is to provide a device that prevents the terminals of a battery module from becoming energized with surrounding conductive parts, even in the event of thermal runaway.

[0007] (II) Technical Solution

[0008] A battery membrane module according to one embodiment includes: a battery cell; a housing covering the battery cell, the housing comprising a conductive material; a busbar electrically connected to the battery cell, the busbar including terminals exposed outside the housing; and a barrier disposed between the terminals and the housing, wherein the barrier may include a groove at its end.

[0009] In one embodiment, the barrier may be disposed in a space spaced apart in a first direction between the terminal block and the housing, and extend in a second direction perpendicular to the first direction, with the groove formed at the end of the barrier in the second direction.

[0010] In one embodiment, the groove may have depth in the second direction.

[0011] In one embodiment, the battery module may further include a cover disposed on the terminal block.

[0012] In one embodiment, the barrier may be configured to surround the edge of the terminal block.

[0013] In one embodiment, the groove may extend along the end of the barrier.

[0014] In one embodiment, the battery module may further include a cover disposed on the barrier, the cover including a protrusion inserted into a groove in the barrier.

[0015] In one embodiment, at least a portion of the barrier may be configured such that the creepage distance between the terminal and the housing is greater than or equal to 12.5 mm and less than or equal to the surface distance or thickness of the barrier.

[0016] In one embodiment, a plurality of the slots may be formed between the terminal block and the housing.

[0017] In one embodiment, the cover may further include a hook formed at an end of the cover, and the barrier may include an engaging portion for receiving the hook.

[0018] A battery membrane module according to one embodiment includes: a plurality of battery cells stacked within a housing; the housing comprising a conductive material; an internal busbar electrically connected to the plurality of battery cells, the internal busbar including at least one terminal protruding beyond the housing and configured to engage with an external busbar; a barrier disposed between the terminal and the housing, the barrier including at least one groove formed at a first end of the barrier; and a cover disposed on the barrier, the cover including at least one protrusion inserted into the at least one groove of the barrier.

[0019] (III) Beneficial Effects

[0020] According to one embodiment of this disclosure, even in the event of thermal runaway, the terminals of the battery module will not be energized with surrounding conductive components. Attached Figure Description

[0021] Figure 1 This is a perspective view of the battery module in the first embodiment.

[0022] Figure 2 This is an exploded perspective view of the battery module in the first embodiment.

[0023] Figure 3 It is magnification Figure 1 The diagram shows the terminal block section.

[0024] Figure 4 yes Figure 3 A cross-sectional view of line I-I'.

[0025] Figure 5 yes Figure 3 The cross-sectional view of line II-II'.

[0026] Figure 6 This is a perspective view of the battery module in the second embodiment.

[0027] Figure 7 It is magnification Figure 6 The diagram shows the terminal block section.

[0028] Figure 8 yes Figure 7 The cross-sectional view of line III-III'.

[0029] Figure 9 yes Figure 7 A cross-sectional view of line IV-IV'.

[0030] Explanation of reference numerals in the attached figures

[0031] 100, 200: Battery module; 110, 210: Battery cell

[0032] 120, 220: Internal busbars; 121, 221: Terminal blocks

[0033] 130, 230: Housing; 140, 240: Insulating components

[0034] 141, 142, 241: Barrier components; 143, 144, 243: Grooves

[0035] 150, 250: Cover Detailed Implementation

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the concept of the present invention is not limited to the embodiments presented.

[0037] For example, those skilled in the art who understand the spirit of the present invention can propose other embodiments that are included within the spirit of the present invention by adding, changing or deleting components, etc., and such embodiments are included within the spirit of the present invention.

[0038] Figure 1 This is a perspective view of the battery module 100 of the first embodiment. Figure 2 This is an exploded perspective view of the battery module 100.

[0039] Reference Figure 1 and Figure 2 The battery module 100 includes a plurality of battery cells 110. The battery cells 110 are stacked in one direction, and each battery cell 110 may include electrode connectors (or electrode leads) 111 extending in a direction perpendicular to the stacking direction. The electrode connectors (or electrode leads) 111 may be connected to an internal busbar 120. For example, the electrode connectors (or electrode leads) 111 of the battery cells 110 may be soldered to the internal busbar 120.

[0040] The battery module 100 includes a housing 130 that houses the battery cells 110. For example, the housing 130 may be configured as a quadrilateral box, with the battery cells 110 arranged in one direction inside the housing. The housing 130 may include an upper plate 131, a lower plate 132, a front plate 133, and a rear plate 134. Figure 2 In the illustrated embodiment, the lower plate 132 may include a bottom planar plate 132b and a vertical side panel 132a. The side panel 132a is also referred to herein as a side panel. As an example, such as Figure 2 As shown, the lower plate 132 can be integrally formed. In a variation of this embodiment, the bottom planar plate 132b and the vertical side panel 132a of the lower plate 132 can be formed separately and joined together by any suitable connector or means. Figure 2As shown, the upper plate 131 and the lower plate 132 can be formed separately or as a single unit. The upper plate 131, the front plate 133, and the rear plate 134 can be formed separately or as a single unit.

[0041] The internal busbar 120 is electrically connected to the electrode connectors (or electrode leads) 111 of the battery cell 110 and to the terminal block 121 exposed outside the housing 130. For example, the terminal block 121 has a shape extending towards the front of the battery module 100, and the terminal block 121 may be exposed in front of the front panel 133. (See reference...) Figure 2 The terminal block 121 is bent at the end of the internal busbar 120 and extends in the +Y direction.

[0042] The battery module 100 is electrically connected via an external busbar, and the external busbar is connected to the internal busbar 120 of the battery module 100 (e.g., the terminal 121 of the internal busbar 120).

[0043] Figure 3 It is magnification Figure 1 The diagram shows the terminal block 121. Figure 4 It is along Figure 3 The cross-sectional view taken from line I-I'. Figure 5 It is along Figure 3 The cross-sectional view taken from line II-II'.

[0044] Refer to this disclosure Figure 3 Terminal block 121 may include a plate having a quadrilateral shape. The upper surface 122 of terminal block 121 contacts an external busbar. The lower surface 123 of terminal block 121 is disposed on an insulating member 140. Terminal block 121 may be bolted to the external busbar. For example, terminal block 121 may include a fastening hole 125 to receive a connector such as a bolt. For example, after an external busbar (not shown) is disposed on the upper surface 122 of terminal block 121, a bolt shank may pass through the external busbar and terminal block 121 and be secured with a nut to engage terminal block 121 and the external busbar. In this disclosure, the upper surface 122 of terminal block 121 refers to the surface facing the +Z direction, and the lower surface 123 refers to the surface facing the -Z direction.

[0045] The housing 130 can be made of a conductive material. For example, the housing 130 can be made of aluminum sheet. In this case, the front panel 133, where the terminals 121 of the internal busbar 120 in the housing 130 are exposed to the outside, must be insulated from the terminals 121. Therefore, a certain insulation distance (air clearance or creepage distance) needs to be ensured between the terminals 121 and the front panel 133.

[0046] In a battery pack comprising multiple battery modules, when any one battery module experiences thermal runaway, gases, flames, and conductive material are dispersed within the battery pack. When the terminal 121 of battery module 100 is exposed to conductive material discharged from another battery module, the insulation between terminal 121 and the front panel 133 may be compromised. For example, conductive byproducts may accumulate around terminal 121, significantly reducing the insulation distance between terminal 121 and the front panel 133. When the insulation between terminal 121 and the front panel 133 is compromised, excessive current flows through the internal circuitry of battery module 100 (e.g., internal busbar 120), potentially causing battery module 100 to catch fire. In other words, an event such as thermal runaway occurring in a particular battery module 100 can lead to a cascading fire in other battery modules 100.

[0047] To prevent such cascading fires, the insulation distance between the terminal block 121 of the battery module 100 and the front panel 133 needs to be set to a value greater than that required under normal operating conditions. That is, even if the insulation distance between the terminal block 121 and the front panel 133 is ensured to be at a level that does not pose a problem under normal operating conditions, the insulation between the terminal block 121 and the front panel 133 may still be compromised in the event of thermal runaway due to the spread of conductive material. Therefore, to ensure that the insulation between the internal busbar 120 and the front panel 133 is not compromised even in the event of thermal runaway, a more conservative insulation distance between the terminal block 121 and the front panel 133 is required.

[0048] The insulation between the front panel 133 and the terminal block 121 can be strengthened by increasing the air clearance and / or creepage distance between the front panel 133 and the terminal block 121. Creepage distance is the shortest distance measured along the surface of the insulating material between two conductive parts. Air clearance distance is the shortest distance measured through air between two conductive parts.

[0049] For example, referring to the standard GB / T16935.1 (IEC60664-1) related to insulation distance, the required creepage distance varies depending on the degree of contamination or the characteristics of the contaminant. For instance, in the case of conductive contamination (Pollution Degree 3) and the presence of a contaminant (material group III) with a high Comparative Tracking Index (CTI), it is necessary to ensure that the creepage distance between conductive components is greater than or equal to 12.5 mm. That is, in the event of thermal runaway, conductive material is dispersed inside the battery pack, therefore the creepage distance between terminal 121 and front panel 133 should be greater than or equal to 12.5 mm. This disclosure provides a technical solution to increase the creepage distance between terminal 121 and front panel 133 to cope with thermal runaway.

[0050] Reference Figure 3 and Figure 4 An insulating component 140 is disposed between the terminal block 121 exposed to the outside of the front panel 133 and the front panel 133. The insulating component 140 strengthens the insulation between the front panel 133 and the terminal block 121.

[0051] In this disclosure, insulating component 140 refers to the portion disposed between the wiring terminal 121 exposed on the outside of the front panel 133 and the front panel 133. However, for ease of description, insulating component 140 of this disclosure may include a portion disposed inside the front panel 133 and not visible from the outside of the battery module 100.

[0052] In one embodiment, the insulating component 140 may include barrier elements 141, 142 disposed between the terminal block 121 and the front panel 133. In one embodiment, the terminal block 121 is positioned at a predetermined distance from the front panel 133, and the barrier elements 141, 142 are located in the space between the terminal block 121 and the front panel 133. The insulation between the front panel 133 and the terminal block 121 is enhanced by the barrier elements 141, 142.

[0053] In one embodiment, when the terminal block 121 is spaced apart from the front panel 133 in a first direction, a barrier 141, 142 extending in a second direction perpendicular to the first direction may be provided between the terminal block 121 and the front panel 133. For example, the barrier 141, 142 may be configured as a wall with thickness in the first direction.

[0054] For example, refer to Figure 4 The terminal block 121 is disposed at a first distance d1 from the front panel 133 in the X direction, and a first barrier 141 extending in the Y direction (or Z direction) may be disposed between the front panel 133 and the terminal block 121. As another example, see... Figure 5The terminal block 121 is provided at a second distance d2 from the front plate 133 in the Z direction, and a second barrier 142 extending in the Y direction (or Z direction) may be provided between the front plate 133 and the terminal block 121.

[0055] The insulating member 140 located between the terminal block 121 and the front panel 133 can be configured to provide a large insulation distance between the terminal block 121 and the front panel 133. In one embodiment, the barriers 141, 142 can be configured to increase the creepage distance between the terminal block 121 and the front panel 133. In one embodiment, at least a portion of the barriers 141, 142 can be configured such that the creepage distance between the terminal block 121 and the front panel 133 is greater than or equal to 12.5 mm.

[0056] To increase creepage distance, in one embodiment, the barrier members 141, 142 may include slots 143, 144 at their ends. In one embodiment, the terminal 121 may be spaced apart from the front panel 133 in a first direction, and the barrier members 141, 142 may extend in a second direction perpendicular to the first direction. In this case, the slots 143, 144 may be provided at the ends of the barrier members 141, 142 in the second direction.

[0057] For example, refer to Figure 4 Terminal block 121 and front plate 133 are spaced apart by a first distance d1 in the X direction, and a first barrier 141 disposed between terminal block 121 and front plate 133 extends in the +Z direction. A first groove 143 is disposed at the end of the first barrier 141 in the +Z direction. As another example, refer to... Figure 5 The terminal block 121 and the front plate 133 are separated by a second distance d2 in the Z direction, and a second barrier 142 provided between the terminal block 121 and the front plate 133 extends in the +Y direction. A second groove 144 is provided at the end of the second barrier 142 in the +Y direction.

[0058] In one embodiment, the slots 143 and 144 may extend along the length of the barrier members 141 and 142. For example, refer to... Figure 4 The first barrier 141 can extend in the Z direction, and the first groove 143 can have depth in the Z direction. As another example, see [reference needed]. Figure 5 The second barrier 142 can extend in the Y direction, and the second groove 144 can have depth in the Y direction.

[0059] Since the creepage distance is measured along the surfaces of the barriers 141 and 142, when the outer surfaces of the barriers 141 and 142 have grooves 143 and 144, the creepage distance between the front panel 133 and the terminal block 121 increases due to the increased surface length caused by the grooves 143 and 144. This helps to strengthen the insulation between the terminal block 121 and the housing 130.

[0060] Reference Figure 4 In one embodiment, the first barrier 141 includes a first groove 143 extending in the Z direction at its end. The creepage distance between the terminal 121 and the front panel 133 is increased by the length of the surface corresponding to the first barrier 141 due to the increase in the first groove 143. The creepage distance between the terminal 121 and a portion of the front panel 133 in the X direction near the terminal 121 can be measured along a first path p1. In one embodiment, at least a portion of the first barrier 141 can be configured such that the length of the first path p1 is greater than or equal to 12.5 mm.

[0061] Compared to the case without the first slot 143, the creepage distance between the terminal block 121 and the front panel 133 is increased by at least twice the depth of the first slot 143, which can enhance the insulation between the terminal block 121 and the front panel 133.

[0062] Reference Figure 5 In one embodiment, the second barrier 142 includes a second groove 144 extending in the Y direction at its end. The creepage distance between the terminal 121 and the front panel 133 is increased by the length of the surface corresponding to the second barrier 142 due to the increase in the second groove 144. The creepage distance between the terminal 121 and a portion of the front panel 133 in the Z direction near the terminal 121 can be measured along the second path p2. In one embodiment, at least a portion of the second barrier 142 can be configured such that the length of the second path p2 is greater than or equal to 12.5 mm.

[0063] Compared to the case without the second slot 144, the creepage distance between the terminal block 121 and the front panel 133 is increased by at least twice the depth of the second slot 143, which can enhance the insulation between the terminal block 121 and the front panel 133.

[0064] exist Figures 1 to 5 In the illustrated embodiment, the first barrier 141 and the second barrier 142 respectively include slots 143 and 144. However, this is merely an example; in another embodiment, multiple slots may be formed between the terminal 121 and the housing 130. For example, the first slot 143 may include two or more slots extending parallel to the end of the first barrier 141. As another example, the second slot 144 may include two or more slots extending parallel to the end of the second barrier 142.

[0065] exist Figures 1 to 5 In the illustrated embodiment, barrier elements 141 and 142 include grooves 143 and 144; however, in another embodiment, barrier elements 141 and 142 may not include grooves 143 and 144. In this case, the thickness of barrier elements 141 and 142 can be greater than that in the illustrated embodiment, such that the creepage distance is greater than or equal to 12.5 mm. For example, in Figure 4 In this embodiment, if the first groove 143 is not present in the first barrier 141, the thickness of the first barrier 141 can be increased to a thickness sufficient to ensure the creepage distance via the first groove 143. In this case, the area of ​​the terminal 121 can be reduced compared to the illustrated embodiment. As another example, in Figure 5 If the second groove 144 is not present in the second barrier 142, the thickness of the second barrier 142 can be increased to the thickness of the creepage distance that can be ensured by the second groove 144.

[0066] Reference Figure 3 In one embodiment, the battery module 100 may further include a cover 150 disposed on the insulating member 140 to cover the terminal block 121. The cover 150 is coupled to the insulating member 140, and the terminal block 121 is located inside the cover 150-insulating member 140 assembly.

[0067] In the event of thermal runaway, even if conductive material is present on the outside of the battery module 100, the cover 150 can minimize or prevent the terminals 121 from being exposed to conductive material.

[0068] In one embodiment, when it is difficult to ensure an insulating distance between the terminal 121 and surrounding metal components (e.g., housing 130) due to the structure of the battery module 100, the area of ​​the terminal 121 can be reduced. The area of ​​the terminal 121 (i.e., the area of ​​the upper surface 122 of the terminal 121) can be reduced to a limit where the internal resistance value requirement between the external busbar and the terminal 121 is not problematic. For example, in high-voltage busbars, according to DIN 43671, the terminal 121 can have a minimum cross-sectional area corresponding to the current value. (Application example: width ≥ 30 mm, thickness ≥ 3 t, current reference 400 A)

[0069] Figure 6 This is a perspective view of the battery module 200 in the second embodiment. Figure 7 It is magnification Figure 6 The diagram shows the terminal block 221. Figure 8 It is along Figure 7 The cross-sectional view taken from line III-III'. Figure 9 It is along Figure 7A cross-sectional view taken from line IV-IV'. Figure 6 The battery module 200 has the same characteristics as... Figure 1 The battery module 100 has a similar structure, and repeated descriptions are omitted.

[0070] Reference Figure 7 In one embodiment, the insulating member 240 may be configured to surround the edge of the terminal 221. In one embodiment, the insulating member 240 may include a barrier 241 surrounding the edge of the terminal 221. For example, the barrier 241 may be provided in the form of a wall (or fence) surrounding the edge of the quadrilateral terminal 221. See also Figure 8 A barrier 241 is provided in the +X and -X directions of the terminal 221, and the barrier 241 protrudes in the +Z direction with reference to the upper surface of the terminal 221. (Refer to...) Figure 9 A barrier 241 is provided in the -Y direction of the terminal block 221.

[0071] In one embodiment, the barrier 241 may include a groove 243 at its end. For example, the barrier 241 may be provided in the form of a wall extending in the Z direction, and the groove 243 may be provided at the +Z end of the wall. Since the creepage distance between the terminal 221 and the front panel 233 is measured along the surface of the barrier 241, it can be longer than in the case without the groove 243. The groove 243 provided at the end of the barrier 241 has a depth in a direction parallel to the extending direction of the barrier 241.

[0072] In one embodiment, the barrier 241 is configured to surround the edge of the terminal 221, and the groove 243 may extend along the end of the barrier 241.

[0073] In one embodiment, the battery module 200 may further include a cover 250 covering the upper surface 222 of the terminal block 221. The cover 250 is coupled to an insulating member 240. For example, the cover 250 may include a hook 255, and the insulating member 240 may include an engagement portion 245 for receiving the hook 255. The terminal block 221 is received in a space 253 defined by the cover 250 and the insulating member 240, such that in the event of thermal runaway, the exposure of the terminal block 221 to conductive material dispersed outside the battery module 200 can be minimized or prevented.

[0074] The battery module 200 is connected via an external busbar, and one end of the external busbar is connected to an internal busbar 220 of a different battery module 200 (specifically, the terminal 221 of the internal busbar 220). Therefore, the insulating component 240 or cover 250 does not completely seal the terminal 221 but is partially open, allowing the external busbar to contact the terminal 221. For example, see reference... Figure 9 The hole 254 for the external busbar can be provided in the cover 250, the insulating component 240, or the cover 250-insulating component 240 assembly.

[0075] The battery module 200 shown is an example where an external busbar extends from terminal 221 to the front of the module, and when the cover 250 is fitted to the insulating member 240, the cover 250 and the insulating member 240 define an opening 254 that opens to the front. However, this is only an example, and in another embodiment, the busbar may have an opening facing the side.

[0076] Reference Figure 8 and Figure 9 In one embodiment, the cover 250 may further include a first protrusion 251 inserted into a groove 243 of the barrier 241. The first protrusion 251 is fitted into the groove 243 to enhance the seal between the cover 250 and the barrier 241, which can prevent or minimize the inflow of external foreign matter (e.g., conductive materials, gases, flames, etc. in the event of thermal runaway) into the inner space 253 of the barrier 241.

[0077] In one embodiment, the cover 250 may further include a second protrusion 252 extending toward an inner or outer surface of the barrier 241. The second protrusion 252 is spaced apart from the first protrusion 251 in an inner or outer direction of the cover 250. The first protrusion 251 and the second protrusion 252 are configured to mate with the end of the barrier 241, which can further enhance the seal between the cover 250 and the barrier 241.

[0078] In the foregoing, the construction and features of the present invention have been described according to embodiments of the present invention. However, the present invention is not limited thereto. Various changes or modifications can be made within the spirit and scope of the present invention, which will be obvious to those skilled in the art. Therefore, such changes or modifications should fall within the scope of the claims.

Claims

1. A battery module, comprising: Battery cell; The housing includes an upper plate, a lower plate, side plates, a front plate, and a rear plate, the housing covering the battery cell, and includes a conductive material; A busbar, electrically connected to the battery cell, the busbar including terminals exposed outside the housing; as well as A barrier element is disposed in a space spaced apart from the terminal block and the front panel in a first direction, and extends in a second direction perpendicular to the first direction. The barrier includes a first end that protrudes further than the surface of the terminal block in the first direction and a second end that protrudes further than the surface of the terminal block in the second direction. Both the first end and the second end include a groove.

2. The battery module according to claim 1, wherein, The groove has a depth in the second direction.

3. The battery module according to claim 1, further comprising: A cover is provided on the terminal block.

4. The battery module according to claim 1, wherein, The barrier is configured to surround the edge of the terminal block.

5. The battery module according to claim 4, wherein, The groove extends along the end of the barrier.

6. The battery module according to claim 5, further comprising: A cover is provided on the barrier. The cover includes a protrusion that inserts into a groove in the barrier.

7. The battery module according to claim 1, wherein, At least a portion of the barrier is configured such that the creepage distance between the terminal and the housing is greater than or equal to 12.5 mm and less than or equal to the surface distance or thickness of the barrier.

8. The battery module according to claim 1, wherein, A plurality of grooves are formed between the terminal block and the front plate.

9. The battery module according to claim 6, wherein, The cover further includes a hook formed at one end of the cover, and The barrier includes a locking portion for receiving the hook.

10. A battery module, comprising: Multiple battery cells are stacked inside the casing; The housing includes an upper plate, a lower plate, side plates, a front plate, and a rear plate, and includes a conductive material; An internal busbar, electrically connected to the plurality of battery cells, the internal busbar including at least one terminal protruding outside the housing and configured to engage with an external busbar; A barrier element is disposed in a space spaced apart in a first direction between the terminal block and the front plate, and extends in a second direction perpendicular to the first direction. as well as A cover is provided on the barrier. The barrier includes a first end that protrudes further than the surface of the terminal block in the first direction and a second end that protrudes further than the surface of the terminal block in the second direction. Both the first end and the second end include grooves. The cover includes at least one protrusion that is inserted into the grooves at the first end and the second end.

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