Battery module and battery pack containing it

Abstract

The present invention includes a battery module and a battery pack including the same, and a battery module according to one embodiment of the present invention includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame including a lower frame on which the battery cell stack is mounted and an upper cover that is coupled to the lower frame while covering the upper part of the battery cell stack; end plates that cover the front and rear of the battery cell stack; heat insulating members that are arranged to cover the upper and both side parts of the module frame and to cover the end plates; and cover members that are positioned on the heat insulating members and are arranged to cover the upper part, both side parts and a portion of the lower part of the module frame and to cover the end plates.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2023 - 0105716, filed on August 11, 2023, and all the contents disclosed in the literature of the Korean patent application are incorporated herein by reference in their entirety.

[0002] The present invention relates to a battery module and a battery pack including the same, and more particularly, to a battery module with improved safety by maintaining the structural stability of the battery module and a battery pack including the same.

Background Art

[0003] As the development of technologies and the demand for mobile devices increase, the demand for secondary batteries as an energy source has been rapidly increasing. Along with this, many studies have been conducted on secondary batteries that can meet various requirements.

[0004] Secondary batteries have attracted much attention not only as an energy source for mobile devices such as mobile phones, digital cameras, and notebook computers, but also as an energy source for power devices such as electric bicycles, electric vehicles, and hybrid electric vehicles.

[0005] In recent years, along with the utilization of secondary batteries as an energy storage source, the need for large - capacity secondary battery structures has been increasing, and the demand for medium - to - large - sized module - structured battery packs formed by aggregating battery modules in which a large number of secondary batteries are connected in series / parallel has been increasing.

[0006] On the other hand, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common to configure a battery module consisting of at least one battery cell, and then use at least one battery module to add other components and configure the battery pack. Since the battery cells that make up such medium- and large-sized battery modules are composed of rechargeable secondary batteries, such high-power, high-capacity secondary batteries generate a large amount of heat during the charging and discharging process. This causes the electrolyte located inside the battery cell to vaporize, increasing the internal pressure and potentially rupturing the battery cell pouch, which can generate exhaust gases and flames. Therefore, it is necessary to prevent this large amount of heat from spreading to adjacent battery modules and from causing those battery modules to explode.

[0007] Figure 1 is a perspective view of a conventional battery module. Figure 2 is an exploded perspective view of a conventional battery module.

[0008] Referring to Figures 1 and 2, a conventional battery module 10 includes a lower frame 11 on which a battery cell stack 22, in which multiple battery cells 21 are stacked, is mounted; an upper frame 12 that is connected to the lower frame 11 while covering the upper part (in the z-axis direction) of the battery cell stack 22; and end plates 50 that cover the front and rear surfaces of the battery cell stack 22.

[0009] In this case, if exhaust gas or flames are generated in the battery cell 21, venting may occur in the gap between the lower frame 11 and the upper frame 12, or between the frame and the end plate 50. In this case, the pressure during venting may cause the structure of the battery module 10 itself to collapse, and flames may transfer to adjacent battery modules 10, potentially leading to an explosion of the entire battery pack.

[0010] Therefore, in order to prevent the problems described above, it is necessary to develop a battery module that can ensure the safety of the battery during venting. [Overview of the project] [Problems that the invention aims to solve]

[0011] The problem that this invention aims to solve is to provide a battery module with improved safety, a battery pack containing the same, and a method for manufacturing the battery module.

[0012] However, the problems that the embodiments of the present invention aim to solve are not limited to those described above, and can be extended to a wide variety of other problems within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0013] A battery module according to one embodiment of the present invention includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame including a lower frame on which the battery cell stack is mounted, and an upper cover that connects to the lower frame while covering the upper part of the battery cell stack; end plates that cover the front and rear surfaces of the battery cell stack; a heat insulating member disposed to cover the upper and both sides of the module frame and to cover the end plates; and a cover member located on the heat insulating member and disposed to cover a portion of the upper, both sides and lower parts of the module frame and to cover the end plates.

[0014] The upper cover includes a plurality of vent holes penetrating the upper cover, and the thermal insulation member includes a first thermal insulation member covering the upper part of the module frame, and the first thermal insulation member may include thermal ruptures which are grooves formed in the first thermal insulation member and are provided at positions corresponding to the vent holes.

[0015] The cover member includes a first cover member that covers the first heat insulating member, and the first cover member may include a cover rupture portion which is a groove formed in the first cover member and is provided at a position corresponding to the vent hole.

[0016] The end plate is positioned such that a terminal busbar electrically connected to the battery cell stack is partially exposed, and the heat insulating member includes a second heat insulating member that covers the front and rear surfaces of the end plate, and the second heat insulating member may include a terminal heat insulating portion that covers the front surface of the terminal busbar.

[0017] The cover member includes a second cover member that covers the second heat insulating member, and the second cover member may include a second-first cover member that covers the terminal heat insulating portion.

[0018] The end plate includes connecting portions located on both sides of the end plate, and the upper and lower surfaces of the connecting portions may be arranged with a height difference from the upper and lower surfaces of the end plate.

[0019] The cover member may include a second cover member that covers the end plate, and the second cover member may include a second-second cover member that covers the upper and lower surfaces of the connecting portion.

[0020] The second cover portion can be formed by bending the second cover member in a direction perpendicular to one surface on the end plate where it is located.

[0021] The thermal insulation member includes a third thermal insulation member that covers both sides of the module frame, and the cover member includes a third cover member that covers the third thermal insulation member, and the third cover member may include a third-first cover portion formed by bending the third cover member in a direction perpendicular to one surface where it is located on the third thermal insulation member.

[0022] The 3-1 cover portion is not covered by the second cover member that covers the end plate, and can cover the front and rear surfaces of the end plate that are exposed to the outside.

[0023] The third cover member can include a third-2 cover portion that is located on both side surfaces of the third cover member and covers the side surfaces of the end plate that are exposed to the outside.

[0024] The third cover member can further include a third-3 cover portion that extends in the length direction of the third-2 cover portion.

[0025] The third-3 cover portion can be bent in a direction perpendicular to one surface where the third-2 cover portion is located on the third heat insulating member, and can cover the front and rear surfaces of the end plate.

[0026] The cover member can include a fourth cover member that is positioned to cover the bottom, which is the lower part of the lower frame.

[0027] The fourth cover member may be an area that extends in the height direction of the second cover member that covers the end plate and the third cover member that covers both side surface portions of the module frame, respectively.

[0028] The fourth cover member may be a portion formed by being bent in a direction perpendicular to one surface where the second cover member is located on the end plate, and may be a portion formed by being bent in a direction perpendicular to one surface where the third cover member is located on both side surface portions of the module frame.

[0029] The heat insulating member can include silicon (Si).

[0030] The cover member can include an insulating material made of mica (MICA) or an inorganic material.

[0031] A battery pack according to another embodiment of the present invention can include the battery module described above. [[ID=3​​​​According to the examples, battery safety can be improved by maintaining the structural stability of the battery module during venting.

[0033] The effects of the present invention are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art from the claims. [Brief explanation of the drawing]

[0034] [Figure 1] This is a perspective view of a conventional battery module. [Figure 2] This is a disassembled perspective view of a conventional battery module. [Figure 3] This is a perspective view of a battery module according to one embodiment of the present invention. [Figure 4] This is an exploded perspective view of a battery module according to one embodiment of the present invention. [Figure 5] This is an exploded perspective view of the battery module of the present invention, excluding the heat insulating member and cover member. [Figure 6] This is a perspective view of a thermal insulation member according to one embodiment of the present invention. [Figure 7] This is a perspective view of a cover member according to one embodiment of the present invention. [Figure 8] Figure 7 is a plan view of the cover member. [Figure 9] Figure 3 shows the battery module viewed from the -z axis direction. [Figure 10] Figure 3 shows the battery module viewed from the x-axis and -x-axis directions. [Figure 11] (a) is a perspective view showing a conventional battery module, and (b) is a perspective view of a battery module according to one embodiment of the present invention. [Figure 12] (a) is a perspective view showing a conventional battery module, and (b) is a perspective view of a battery module according to one embodiment of the present invention. [Figure 13] Figure 3 shows the battery module viewed from the y-axis and -y-axis directions. [Figure 14]Figure 3 shows the battery module as viewed from the z-axis direction. [Modes for carrying out the invention]

[0035] The following describes various embodiments of the present invention in detail, with reference to the attached drawings, so that those with ordinary skill in the art to which the present invention pertains can easily implement them. The present invention can be embodied in various different forms and is not limited to the embodiments described herein.

[0036] To clearly explain the present invention, unnecessary parts have been omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

[0037] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrarily shown for illustrative purposes, and therefore the present invention is not necessarily limited to those shown. In the drawings, the thicknesses of some layers and regions are shown enlarged to clearly represent them. Also, in the drawings, the thicknesses of some layers and regions are shown exaggerated for illustrative purposes.

[0038] Furthermore, when a layer, membrane, region, plate, or other part is "on top of" or "above" another part, this includes not only when it is "directly above" the other part, but also when there are other parts in between. Conversely, when one part is "directly above" another part, it means that there are no other parts in between. Also, being "on top of" or "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "on top of" or "above" in the opposite direction of gravity.

[0039] Furthermore, when a specification states that a part of it "includes" a certain component, unless otherwise specified, this means that it may include other components, rather than excluding them.

[0040] Furthermore, throughout the specification, "on a plane" means when the subject is viewed from above, and "on a cross-section" means when the subject is viewed from the side of a cross-section obtained by cutting the subject perpendicularly.

[0041] Furthermore, while the first and second terms used in this application may be used to describe various components, the components should not be limited by the terms. The terms are used solely for the purpose of distinguishing one component from another.

[0042] Furthermore, in this application, the upper and lower parts are defined as the z-axis and -z-axis directions, respectively; the sides as the y-axis and -y-axis directions; and the front and rear as the x-axis and -x-axis directions, respectively. However, these definitions are arbitrary and made for convenience within the specification, and the scope of the rights is not limited to these names.

[0043] Figure 3 is a perspective view of a battery module according to one embodiment of the present invention. Figure 4 is an exploded perspective view of a battery module according to one embodiment of the present invention. Figure 5 is an exploded perspective view of the battery module excluding the heat insulating member and cover member of the present invention.

[0044] Referring to Figures 3 and 4, a battery module 100 according to one embodiment of the present invention includes a battery cell stack 120 in which a plurality of battery cells 110 are stacked, a module frame 200 that houses the battery cell stack 120, end plates 250 that cover the front and rear surfaces of the battery cell stack 120, and a heat insulating member 300 and a cover member 400 that cover the module frame 200 and the end plates 250.

[0045] Referring to Figures 3 to 5, first, the battery cell 110 may be a pouch-type battery cell. Such a pouch-type battery cell may be formed by housing an electrode assembly in a pouch case made of a laminate sheet containing a resin layer and a metal layer, and then heat-sealing the pouch case. In this case, the battery cell 110 may be formed in a rectangular sheet-type structure. However, the battery cell 110 is not limited to a pouch-type battery cell, and may be various types of battery cells.

[0046] Multiple such battery cells 110 may be configured, and multiple battery cells 110 are stacked so as to be electrically connected to each other to form a battery cell stack 120. In particular, as shown in Figure 5, multiple battery cells 110 may be stacked along a direction parallel to the y-axis.

[0047] The module frame 200 that houses the battery cell stack 120 may include an upper cover 220 and a lower frame 210.

[0048] The lower frame 210 may include a bottom portion 210a and two side portions 211 extending upward from both ends of the bottom portion 210a. The bottom portion 210a can cover the bottom surface (-z axis direction) of the battery cell stack 120, and the side portions 211 can cover both sides (y axis direction and -y axis direction) of the battery cell stack 120.

[0049] A thermally conductive resin layer 213 can be positioned at the bottom 210a of the lower frame 210. The thermally conductive resin layer 213 is positioned between the battery cell stack 120 and the bottom 210a of the lower frame 210, allowing the battery cell stack 120 to be fixedly positioned at the bottom 210a of the lower frame 210.

[0050] The upper cover 220 may be formed as a single plate-like structure that covers the remaining upper part (in the z-axis direction) of the battery cell stack 120, excluding the lower part and both sides which are covered by the lower frame 210. The upper cover 220 and the lower frame 210 can be joined by welding or other means with their corresponding edge portions in contact to form a structure that covers the battery cell stack 120 from all sides (up, down, left, and right).

[0051] The upper cover 200 may include vent holes 221, which are multiple holes that penetrate the upper cover 200. The vent holes 221 may also be holes that penetrate the upper cover 200 in the height direction (z-axis direction). This allows exhaust gases, flames, etc., generated in the battery cell 110 to be discharged to the outside of the module frame 200 through the vent holes 221.

[0052] The module frame 200 can physically protect the battery cell stack 120. For this purpose, the module frame 200 may include a metal material having a predetermined strength.

[0053] On the other hand, although specific illustrations are omitted, the modified module frame 200 may be a monoframe in the form of a metal plate with the top, bottom, and both sides integrated. That is, instead of a structure in which the lower frame 210 and the upper cover 220 are joined to each other, it may be a structure in which the top, bottom, and both sides are integrated, manufactured by extrusion molding. Furthermore, the structure of the module frame 200 may be provided as a monoframe or as an L-shaped frame in addition to the lower frame, and may be provided in various structures not described in the above examples.

[0054] The structure of such a module frame 200 may be provided in an open form along the longitudinal direction of the battery cell stack 120. That is, the front (x-axis direction) and rear (-x-axis direction) of the battery cell stack 120 do not have to be covered by the module frame 200. Therefore, the front and rear of the battery cell stack 120 are shielded by the busbar assembly 130 and end plates 250, etc., thereby protecting the front and rear of the battery cell stack 120 from external physical impacts and the like.

[0055] The busbar assembly 130 includes a busbar frame and a busbar mounted on one surface of the busbar frame.

[0056] The busbar frame may be located on the front and / or rear surface of the battery cell stack 120, covering one side of the battery cell stack 120 and guiding the connection between the battery cell stack 120 and external equipment. The busbar may be mounted on one side of the busbar frame and electrically connecting the battery cell stack 120 or battery cells 110 to external equipment circuits.

[0057] The busbar may include a terminal busbar 135 for electrically connecting one battery module 100 to another battery module 100. That is, at least a portion of the terminal busbar 135 can be exposed outside the end plate 250 so that one battery module 100 can be connected to an adjacent battery module 100.

[0058] The terminal busbar 135 can be connected to other battery modules 100 or BDUs (Battery Disconnect Units) via protrusions exposed to the outside of the end plate 250, thereby forming a high-voltage (HV) connection with them.

[0059] The end plate 250 may also serve to protect the battery cell stack 120 and the electrical components connected thereto from external physical shocks by sealing the open surface of the module frame 200. For this purpose, the end plate 250 may be made of a material having a predetermined strength. For example, the end plate 250 may include a metal such as aluminum.

[0060] The end plate 250 may include a connecting portion 270 that can connect and fix the battery module 100 and the pack frame with a fastening member. In other words, the connecting portion 270 can connect and fix the end plate 250 and the battery pack with a fastening member.

[0061] The connecting portion 270 can be located on both sides of the end plate 250. The connecting portion 270 includes a hole that penetrates the battery module 100 in the height direction (z-axis direction), and a fastening member can pass through the hole to be positioned. That is, the fastening member can fixatively connect the battery module and the pack frame via the connecting portion 270, allowing the battery module 100 to be positioned more firmly on the battery pack and improving the mechanical stability of the battery.

[0062] The end plate 250 may cover the busbar assembly 130 located on one surface of the battery cell stack 120 and be coupled (joined, sealed or sealed) to the module frame 200.

[0063] The thermal insulation member 300 can be positioned to cover the module frame 200. Specifically, the thermal insulation member 300 can be positioned to cover the top, both sides, front and rear of the module frame 200. The thermal insulation member 300 is made of a thermally insulating material and can prevent heat transfer between one battery module 100 and an adjacent battery module 100. Therefore, even if the temperature of one battery module 100 rises, heat can be transferred to the adjacent battery module 100, preventing the temperature of the adjacent battery module 100 from rising and preventing thermal runaway phenomena from occurring due to the temperature rise.

[0064] The thermal insulation member 300 will be explained in more detail in Figure 6.

[0065] The cover member 400 can be positioned to cover the module frame 200 and the heat insulating member 300. Specifically, the cover member 400 can be positioned to cover the entire outer surface of the heat insulating member 300 and at least a portion of the lower part (in the -z-axis direction) of the module frame 200. In this case, the cover member 400 can be positioned to cover a portion of the bottom 210a of the lower frame 210.

[0066] The cover member 400 is positioned to cover the module frame 200 and the heat insulating member 300, thereby ensuring insulation from adjacent battery modules 100 and battery packs even when thermal runaway occurs in the battery module 100, and thus ensuring the safety of the battery.

[0067] Furthermore, since the cover member 400 is positioned to cover a portion of the bottom 210a of the module frame 200, even if venting occurs in the battery cell stack 120 and the pressure inside the battery module 100 rises, the cover member 400 can be prevented from detaching or peeling off from the module frame 200. Therefore, the insulation of the battery module 100 can be ensured even during venting.

[0068] The cover member 400 will be explained in more detail in Figures 7 and 8.

[0069] Figure 6 is a perspective view of a thermal insulation member according to one embodiment of the present invention.

[0070] Referring to Figures 4 and 6, the heat insulating member 300 according to one embodiment of the present invention is positioned to cover the module frame 200.

[0071] The thermal insulation member 300 includes a first thermal insulation member 310 covering the top (z-axis direction) of the module frame 200, a second thermal insulation member covering both sides (y-axis direction and -y-axis direction) of the module frame 200, and a third thermal insulation member 303 covering the front and rear surfaces (x-axis direction and -x-axis direction) of the module frame 200. In this case, the first thermal insulation member 310, the second thermal insulation member 320, and the third thermal insulation member 330 can be positioned to cover the outer circumferential surface of the module frame 200, respectively.

[0072] The first thermal insulation member 310 may include a thermal rupture section 311.

[0073] The adiabatic rupture section 311 is a groove formed in the first adiabatic member 310, and by rupturing due to internal pressure, exhaust gases and flames generated in the battery cell stack 120 can be discharged to the outside.

[0074] Multiple thermal ruptures 311 may be formed in the first thermal insulation member 310. Specifically, the thermal ruptures 311 may be grooves formed in a region of the first thermal insulation member 310 facing the vent holes 221 of the upper cover 220. Therefore, the number and size of the thermal ruptures 311 can correspond to the number and size of the vent holes 221. The number of thermal ruptures 311 may be the same as the number of vent holes 221, and the size of the thermal ruptures 311 may be the same as the size of the vent holes 221, or it may be smaller.

[0075] In this figure, the adiabatic rupture section 311 is shown as a single straight line with both ends of the line divided into two parts. However, it is not limited to this shape and can be changed to any shape that corresponds to the size of the vent hole 221.

[0076] If exhaust gas or flame is generated in one battery cell 110, these can only move to the outside of the module frame 200 through some of the multiple vent holes 221. In this case, only the adiabatic rupture section 311 located at the position corresponding to the some vent holes 221 to which the exhaust gas or flame has moved may rupture due to internal pressure. This separates the battery cell stack 120 from the external environment by causing only some of the multiple adiabatic rupture sections 311 to rupture while others do not, thus preventing exhaust gas, flame, and high-temperature particles from flowing back into the module frame 200. Therefore, exhaust gas, flame, and high-temperature particles discharged to the outside may not affect the normal battery cells 110, thereby improving battery safety.

[0077] The second heat insulating member 320 may include a terminal heat insulating section 321.

[0078] The terminal insulation portion 321 may be configured to cover a portion of the terminal bus bar 135 that is exposed to the outside of the end plate 250. Specifically, the terminal insulation portion 321 may be configured to cover the front surface (x-axis direction) of the terminal bus bar 135 that is exposed to the outside of the end plate 250.

[0079] The terminal busbar 135 is inevitably exposed due to the electrical connection between one battery module and an adjacent battery module. Generally, the battery modules are electrically connected via the upper surface (z-axis direction) of the terminal busbar 135. In this case, the side surface of the terminal busbar 135 can be exposed to the outside without being used for electrical connection with other battery modules, and this area can be covered via the terminal insulation section 321. This prevents short circuits with adjacent battery modules. Furthermore, if a thermal runaway phenomenon occurs in one battery module, it is possible to prevent heat transfer or flame transfer to the other battery module and prevent backflow of exhaust gas and flame, thereby improving the safety of the battery.

[0080] The thermal insulation member 300 may be made of a material that has thermal insulation properties. For example, the thermal insulation member 300 may be made of silicon (Si).

[0081] In summary, the insulating material 300 covers the top, both sides, front, and rear of the module frame 200, thereby protecting the module frame 200 from exhaust gases and flames when it is exposed to the outside in the event of a thermal runaway. Furthermore, by covering components that are inevitably exposed to the outside as much as possible, backflow of exhaust gases and flames can be prevented, thereby improving the safety of the battery.

[0082] Figure 7 is a perspective view of a cover member according to one embodiment of the present invention. Figure 8 is a plan view of the cover member of Figure 7.

[0083] Referring to Figures 4, 7, and 8, the cover member 400 according to one embodiment of the present invention is positioned to cover the module frame 200 and the heat insulating member 300.

[0084] The cover member 400 includes a first cover member 410 that covers the top (z-axis direction) of the heat insulating member 300, a second cover member 420 that covers both sides (y-axis direction and -y-axis direction) of the heat insulating member 300, a third cover member 430 that covers the front and rear surfaces (x-axis direction and -x-axis direction) of the heat insulating member 300, and a fourth cover member 440 that covers the bottom 210a of the module frame 200. In this case, the first cover member 410, the second cover member 420, and the third cover member 430 can be positioned to cover the outer circumferential surface of the heat insulating member 300, respectively, and the fourth cover member 440 can be positioned to partially cover the bottom 210a of the module frame 200.

[0085] The first cover member 410, the second cover member 420, the third cover member 430, and the fourth cover member 440 are all connected together and may be folded and separated to correspond to the shape of the module frame. Specifically, the first cover member 410, the second cover member 420, the third cover member 430, and the fourth cover member 440 may be folded and separated along the dotted lines shown in Figure 8.

[0086] The cover member 400 may be formed from a fire-resistant and / or flame-retardant material. For example, the cover member 400 may include an insulating material made of mica or an inorganic material. Such a cover member 400 can withstand temperatures of approximately 1000 degrees or higher and can improve battery stability by preventing short circuits that may occur between one battery module and an adjacent battery module, or between a battery module and a battery pack.

[0087] Figure 9 shows the battery module from Figure 3 viewed from the -z axis direction.

[0088] Referring to Figures 4 and 7-9, the first cover member 410 according to one embodiment of the present invention is positioned to cover the upper part (in the z-axis direction) of the battery module 100.

[0089] The first cover member 410 can be positioned to cover the upper cover 220 of the module frame 200 located above the battery module and the upper part (in the z-axis direction) of the heat insulating member 300.

[0090] Since the first cover member 410 can be positioned to completely cover the outer circumferential surface of the upper cover 220, the size of the first cover member 410 may be the same as or larger than the size of the upper cover 220. Also, since the first cover member 410 can be positioned to completely cover the upper part of the heat insulating member 300, the size of the first cover member 410 may be the same as or larger than the upper part of the heat insulating member 300.

[0091] The first cover member 410 may include a plurality of cover rupture portions 411.

[0092] The cover rupture section 411 is a groove formed in the first cover member 410, which allows exhaust gases, flames, etc., discharged through the vent hole 221 of the cover 220 and the heat insulating rupture section 311 of the heat insulating member 300 to be discharged to the outside. At this time, the cover rupture section 411 ruptures due to the internal pressure that rises due to the exhaust gases, flames, etc., thereby allowing these to be discharged to the outside.

[0093] The cover rupture section 411 may be a plurality of grooves formed in the first cover member 410. Specifically, the cover rupture section 411 may be a plurality of grooves formed in one area of ​​the first cover member 410 facing the vent hole 221 provided in the upper cover 220. Alternatively, the cover rupture section 411 may be a plurality of grooves formed in one area of ​​the first cover member 410 facing the thermal insulation rupture section 311 provided on the upper part of the thermal insulation member 300. Therefore, the cover rupture section 411 can be provided at positions corresponding to the plurality of vent holes 221 and thermal insulation rupture section 311, respectively.

[0094] The cover rupture section 411 may be a groove formed in the same shape as the vent hole 221 provided in the upper cover 220. Therefore, when the cover rupture section 411 ruptures due to internal pressure, it can form a hole with the same shape as the vent hole 221. However, the shape of the cover rupture section 411 is not limited to this and can be changed to any shape that can be modified by an ordinary engineer.

[0095] If exhaust gases or flames are generated in a single battery cell 110, these can only move to the outside of the module frame 200 through some of the multiple vent holes 221. In this case, only the adiabatic rupture section 311 located at the position corresponding to the some vent holes 221 through which the exhaust gases or flames have moved can rupture due to the internal pressure. The exhaust gases or flames that have moved through the adiabatic rupture section 311 located at the position corresponding to the some vent holes 221 may be discharged to the outside by rupturing a cover rupture section 411 located at the corresponding position.

[0096] As a result, only some of the multiple cover rupture points 411 rupture, while the others do not, thus separating the battery cell stack 120 from the external environment. This prevents exhaust gases, flames, and high-temperature particles from flowing back into the module frame 200. Therefore, exhaust gases, flames, and high-temperature particles discharged to the outside may not affect the normal battery cells 110, thereby improving battery safety.

[0097] Referring to Figure 9, when the battery module 100 is viewed from above in the z-axis direction, the exposed portion of the module frame 200, excluding the terminal bus bar 135, may be covered by the first cover member 410 and the folding cover portion 423a.

[0098] Here, the folding cover portion 423a constitutes the second cover member 420, which will be discussed in detail below while explaining the second cover member 420.

[0099] Figure 10 shows the battery module of Figure 3 viewed from the x-axis and -x-axis directions. Figures 11(a) and 12(a) are perspective views showing a conventional battery module. Figures 11(b) and 12(b) are perspective views of a battery module according to one embodiment of the present invention.

[0100] Referring to Figures 4, 7, 8, and 10, the second cover member 420 according to one embodiment of the present invention can be positioned to cover the front (x-axis direction) and rear (-x-axis direction) of the battery module.

[0101] The second cover member 420 can be positioned to cover the end plate 250 and the heat insulating member 300 located on one side (in the x-axis direction) and the other side (in the -x-axis direction) of the battery module 100. One side of the battery module 100 may be the front surface of the battery module 100, and the other side of the battery module 100 may be the other surface of the battery module 100. Here, Figure 10(a) shows that the second cover member 420 is positioned to cover the front surface of the battery module 100 of the present invention, and Figure 10(b) shows that the second cover member 420 is positioned to cover the rear surface of the battery module 100 of the present invention.

[0102] Since the second cover member 420 can be positioned to cover the entire outer surface of the end plate 250, the size of the second cover member 420 may be the same as or larger than the size of the end plate 250. Also, since the second cover member 420 can be positioned to cover the entire front and rear surfaces of the heat insulating member 300, the size of the second cover member 420 may be the same as or larger than the size of the heat insulating member 300.

[0103] In this case, the second cover member 420 that covers the front of the battery module 100 where the terminal busbar 135 is located may include a second-first cover portion 421 and a second-second cover portion 423.

[0104] The second-first cover portion 421 may be configured to cover a portion of the terminal bus bar 135 that is exposed to the outside of the end plate 250. Specifically, the second-first cover portion 421 may be configured to cover a heat insulating member 300 that covers a portion of the terminal bus bar 135 that is exposed to the outside of the end plate 250. Here, the heat insulating member 300 that covers a portion of the terminal bus bar 135 may be the terminal heat insulating portion 321 (see Figure 6).

[0105] The second-first cover portion 421 may be configured to cover a portion of the terminal busbar 135 that is exposed to the outside and is not used for electrical connection between battery modules. Specifically, the second-first cover portion 421 can be positioned to again cover the terminal insulation portion 321 of the insulation member 300.

[0106] Referring to Figures 11(a) and 12(a), in the conventional battery module 10, the terminal busbar 13 is mounted on the end plate 50 located on the front (x-axis direction) with a portion of it exposed to the outside. Specifically, in the conventional battery module 10, the terminal busbar 13 is exposed to the outside not only on the top surface for electrical connection with the battery module, but also on the sides. In other words, unlike the battery module 100 according to one embodiment of the present invention, the conventional battery module 10 does not have an insulating member or cover member to cover the end plate 50 and the terminal busbar 13, so there was a problem that the terminal busbar 15 could short-circuit with other battery modules or battery packs. Furthermore, if exhaust gas or flames are generated in an adjacent battery module and discharged to the outside, there was a problem that the exhaust gas or flames could flow into the assembly tolerances between the terminal busbar 13 and the end plate 50, or between the terminal busbar 13 and the module frames 11 and 12, potentially causing an explosion, thus reducing the safety of the battery.

[0107] In contrast, referring to Figures 11(b) and 12(b), it can be seen that in one embodiment of the present invention, the battery module 100 covers the module frame not only with a heat insulating member but also with a cover member 400. Specifically, the second cover member 420 covers the front of the battery module 100, and at this time, the second-first cover member 421 covers up to the side of the terminal bus bar 135. That is, by covering the side of the terminal bus bar 135 that is unnecessarily exposed to the outside with the second-first cover member 421, it is possible to prevent a short circuit from occurring between one battery module and adjacent battery modules or battery packs. Furthermore, in the event that exhaust gas or flames are generated in an adjacent battery module and discharged to the outside, unlike the conventional battery module 10, the second cover member 420 covers the tolerances of the components assembled to the terminal bus bar 13, thereby preventing the inflow of exhaust gas or flames and improving the safety of the battery.

[0108] Referring again to Figures 4, 7, and 8, the second-second cover portion 423 may be located on both sides of the second cover member 420 and may be formed by bending the second cover member 420 in a direction perpendicular to one surface on which it is located on the end plate 250. In this case, the second-second cover portion 423 can be positioned to cover the connecting portion 270 of the end plate 250. Specifically, the second-second cover portion 423 can be positioned to cover the upper surface (in the z-axis direction) and the lower surface (in the -z-axis direction) of the connecting portion 270.

[0109] In a battery module 100 according to one embodiment of the present invention, the upper and lower surfaces of the connecting portion 270 are arranged with a height difference from the upper and lower surfaces of the end plate 250, and therefore may not be covered by the first cover member 410 or the fourth cover member 440. Consequently, the second-second cover portion 423 can be positioned to cover the connecting portion 270 in order to prevent exhaust gases, flames, etc. from flowing into the battery module 100 when the upper and lower surfaces of the connecting portion 270 are inevitably exposed to the outside.

[0110] Referring to Figures 11(a) and 12(a), the end plate 50 that covers the front and rear (x-axis and -x-axis) of the conventional battery module 10 may include connecting portions 51 provided on both sides of the end plate 250. In this case, not only the connecting portions 51, but also the end plate 50 and module frames 11 and 12 may all be exposed to the outside.

[0111] In other words, unlike the battery module 100 according to one embodiment of the present invention, the conventional battery module 10 is not provided with heat insulating material or cover material to cover the end plate 50, connecting portion 51, module frame 11, 12, etc. Therefore, if exhaust gas or flames are generated in an adjacent battery module and discharged to the outside, there is a possibility that the exhaust gas or flames may flow into the assembly tolerance of the end plate 50 and module frame 11, 12, which are unavoidably exposed to the outside, potentially causing an explosion or other problem, thus reducing the safety of the battery. In addition, if thermal runaway occurs and the external shape of the battery module 10 collapses, there is a risk of short circuits occurring between battery modules or between battery modules and battery packs.

[0112] In contrast, referring to Figures 11(b) and 12(b), it can be seen that in the battery module 100 of the present invention, the cover member 400 covers not only the module frame 200 but also the connecting portion 270 of the end plate 250. Specifically, the second cover member 420 covers the front and rear surfaces of the battery module 100, and the second-second cover portion 423, which is folded while connected to the second cover member 420, can cover the upper and lower surfaces of the connecting portion 270.

[0113] In this case, the second-second cover portion 423 may include a first foldable cover portion 423a that covers the upper surface of the connecting portion 270 and a second foldable cover portion 423b that covers the lower surface of the connecting portion 270. By positioning the first foldable cover portion 423a and the second foldable cover portion 423b to cover the upper and lower surfaces of the connecting portion 270 that are inevitably exposed to the outside, exhaust gases, flames, etc., can be prevented from entering the battery module 100, thereby preventing thermal runaway phenomena. Furthermore, even if thermal runaway phenomena occur and the external shape of the battery module 100 collapses, the second-second cover portion 423 is positioned to cover both the upper and lower surfaces of the connecting portion 270, thereby preventing short circuits between battery modules and between battery modules and the pack, and improving the safety of the battery.

[0114] Referring to Figures 4, 7, 8, and 13, the third cover member 430 according to one embodiment of the present invention can be positioned to cover both sides (y-axis direction and -y-axis direction) of the battery module 100.

[0115] The third cover member 430 can be positioned to cover the side portions 211 (see Figure 5) of the module frame 200 and the side portions of the heat insulating member 300, which are located on both sides of the battery module. In other words, the third cover member 430 can be positioned to cover the third heat insulating member 330 (see Figure 6).

[0116] Since the third cover member 430 can be positioned to cover the entire outer surface of the side portion 211 of the module frame 200, the size of the third cover member 430 may be the same as or larger than the size of the side portion 211. Also, since the third cover member 430 can be positioned to cover both side portions of the heat insulating member 300, the size of the third cover member 430 may be the same as or larger than the size of both side portions of the heat insulating member 300.

[0117] The third cover member 430 may include a third-first cover portion 431 and a third-second cover portion 433.

[0118] Referring to Figures 8, 11(b), and 12(b), the third-first cover portion 431 is located on both sides of the third cover member 430 and may be formed by bending the third cover member 430 in a direction perpendicular to one surface on which it is located on the third heat insulating member 330. In this case, the third-first cover portion 431 can be positioned to cover the end plate 250. Specifically, the third-first cover portion 431 can be positioned to cover a portion of the end plate 250 that is exposed to the outside without being covered by the first cover member 410. Here, the portion of the end plate 250 covered by the third-first cover portion 431 may be the front portion of the end plate 250 at a position corresponding to the upper and lower surfaces of the connecting portion 270.

[0119] Referring to Figures 8, 11(b), 12(b), and 13, the third-second cover portion 433 may be located on both sides (in the x-axis direction and the -x-axis direction) of the third cover member 430 and cover the sides (in the y-axis direction and the -y-axis direction) of the end plate 250 that are exposed to the outside. Here, the side of the end plate 250 covered by the third cover member 430 may be the connecting portion 270.

[0120] Specifically, the third-second cover portion 433 can be positioned to cover a portion of the connecting portion 270 that is not covered by the first cover member 410 and is exposed to the outside. In this case, the portion of the connecting portion 270 may be the side surface of the connecting portion 270.

[0121] The third-second cover portion 433 is located on both sides of the third cover member 430 and can cover the connecting portion 270, as shown in Figure 13. However, it may also further include a third-third cover portion 435 extending in the longitudinal direction (x-axis direction and -x-axis direction) of the third-second cover portion 433, as shown in Figures 11(b) and 12(b).

[0122] The third-third cover portion 435 can be positioned to cover the front and rear surfaces of the end plate 250 by bending the third-second cover portion 433 in a direction perpendicular to the side surface of the module frame 200, that is, the surface located on the third heat insulating member 330 (see Figure 6). Specifically, the third-third cover portion 435 can be positioned to surround a part of the first cover member 410 that covers the front and rear surfaces of the end plate 250.

[0123] In this case, since the third-third cover portion 435 is positioned to again surround a region of the first cover member 410, a region of the battery module 100 that is exposed to the outside is more reliably protected, thereby preventing short circuits between the battery module and other electrical components and preventing the inflow of exhaust gases, flames, etc., and improving the safety of the battery.

[0124] Figure 14 is a view of the battery module shown in Figure 3 from the z-axis direction.

[0125] Referring to Figures 8, 12(b), and 14, the fourth cover member 440 according to one embodiment of the present invention can be positioned to cover the bottom portion 210a of the battery module 100, which is the lower part (-z axis direction). Specifically, the fourth cover member 440 can be positioned to partially cover the bottom portion 210a of the battery module 100.

[0126] The fourth cover member 440 is a region where the second cover member 420 and the third cover member 430 extend in the height direction (z-axis direction), and may be a portion formed by bending the second cover member 420 and the third cover member 430 in a direction perpendicular to one surface located on the battery module 100. That is, the fourth cover member 440 may be a portion formed by bending the second cover member 420 in a direction perpendicular to one surface located on the end plate 250, or a portion formed by bending the third cover member 430 in a direction perpendicular to one surface located on both sides of the module frame 200.

[0127] Since the fourth cover member 440 is positioned to cover only a portion of the bottom 210a, adhesive (not shown) is applied to the area of ​​the bottom 210a where the fourth cover member 440 is not located, allowing the battery module 100 to be fixedly positioned on the battery pack frame. This allows the cover member 400 to cover the assembly tolerance between the module frame and the end plate that constitute the battery module 100 to the greatest extent possible, while simultaneously ensuring the fixing force between the battery module 100 and the battery pack, thereby improving both the safety and mechanical stability of the battery.

[0128] Conventional battery modules 10 (see Figures 1 and 2) not only lacked a configuration that covered the module frame like the cover member 400 of the present invention, but even if they had a configuration corresponding to the cover member 400, it was common for them not to cover the bottom of the battery module. In other words, even if a conventional battery module had a configuration corresponding to the cover member 400 of the present invention, it only covered the top, both sides, front and rear of the battery module, and did not cover the bottom.

[0129] In contrast, the cover member 400 according to one embodiment of the present invention includes a fourth cover member 440, and can therefore cover not only the top, both sides, front, and rear of the battery module 100, but also the bottom. In this case, by positioning the cover member 400 to hang from the bottom of the battery module 100, it is possible to prevent the cover member 400 from detaching from the battery module 100 even if high pressure is applied from the inside to the outside of the cover member 400 due to thermal runaway or the like. Furthermore, it is possible to prevent flames and exhaust gases from flowing into the assembly tolerances between the module frame and end plates, and heat transfer can be more effectively delayed, thereby improving the safety of the battery.

[0130] The aforementioned battery modules and battery packs containing them can be applied to a variety of devices. Such devices can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto and is applicable to a variety of devices that can use battery modules and battery packs containing them, and these also fall within the scope of the present invention.

[0131] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements by those skilled in the art, utilizing the basic concepts of the present invention as defined in the claims below, also fall within the scope of the present invention. [Explanation of symbols]

[0132] 100 Battery Modules 135 Terminal Bus Bar 200 Module Frames 210 Lower frame 220 Top cover 221 Venthole 250 End Plate 270 Connection section 300 Insulation material 400 Cover component 410 First cover member 411 Cover rupture 420 Second cover member 421 Section 2-1 Cover 423 Section 2-2 Cover 430 Third cover member 431 Section 3-1 Cover 433 Section 3-2 Cover 440 Fourth cover member

Claims

1. A battery cell stack, in which multiple battery cells are stacked; A module frame including a lower frame on which the battery cell stack is mounted, and an upper cover that connects to the lower frame while covering the upper part of the battery cell stack; End plates that cover the front and rear of the battery cell stack; A heat insulating member positioned to cover the upper and both sides of the module frame, and to cover the end plate; and A cover member positioned on the aforementioned heat insulating member, covering a portion of the upper, both sides, and lower parts of the module frame, and covering the end plate; A battery module including this.

2. The upper cover includes a plurality of vent holes that penetrate the upper cover, The aforementioned heat insulating member includes a first heat insulating member that covers the upper part of the module frame, The battery module according to claim 1, wherein the first insulating member is provided at a position corresponding to the vent hole and includes an insulating rupture portion which is a groove formed in the first insulating member.

3. The cover member includes a first cover member that covers the first heat insulating member, The battery module according to claim 2, wherein the first cover member is provided at a position corresponding to the vent hole and includes a cover rupture portion which is a groove formed in the first cover member.

4. The end plate has terminal busbars that are electrically connected to the battery cell stack positioned with a portion of them exposed. The aforementioned heat insulating member includes a second heat insulating member that covers the front and rear surfaces of the end plate. The battery module according to claim 1, wherein the second heat insulating member includes a terminal heat insulating portion that covers the front surface of the terminal busbar.

5. The cover member includes a second cover member that covers the second heat insulating member. The battery module according to claim 4, wherein the second cover member includes a second-first cover portion that covers the terminal insulation portion.

6. The end plate includes connecting portions located on both sides of the end plate, The battery module according to claim 1, wherein the upper and lower surfaces of the connecting portion are arranged with a height difference from the upper and lower surfaces of the end plate.

7. The cover member includes a second cover member that covers the end plate. The battery module according to claim 6, wherein the second cover member includes a second-second cover portion that covers the upper and lower surfaces of the connecting portion.

8. The battery module according to claim 7, wherein the second-second cover portion is formed by bending the second cover member in a direction perpendicular to one surface located on the end plate.

9. The aforementioned heat insulating member includes a third heat insulating member that covers both sides of the module frame. The cover member includes a third cover member that covers the third heat insulating member. The battery module according to claim 1, wherein the third cover member includes a third-first cover portion formed by bending the third cover member in a direction perpendicular to one surface on which it is located on the third heat insulating member.

10. The battery module according to claim 9, wherein the 3-1 cover portion is not covered by the second cover member that covers the end plate, and covers the front and rear surfaces of the end plate that are exposed to the outside.

11. The battery module according to claim 9, wherein the third cover member includes a third-second cover portion located on both sides of the third cover member and covering the side of the end plate exposed to the outside.

12. The battery module according to claim 11, wherein the third cover member further includes a third-third cover portion extending in the longitudinal direction of the third-second cover portion.

13. The battery module according to claim 12, wherein the 3-3 cover portion is bent in a direction perpendicular to one surface of the 3-2 cover portion located on the 3 heat insulating member, and covers the front and rear surfaces of the end plate.

14. The battery module according to claim 1, wherein the cover member includes a fourth cover member positioned to cover the bottom portion which is the lower part of the lower frame.

15. The battery module according to claim 14, wherein the fourth cover member is a region extending in the height direction from the second cover member that covers the end plate and the third cover member that covers both sides of the module frame.

16. The fourth cover member is, The portion of the second cover member is formed by bending it in a direction perpendicular to one surface located on the end plate, The battery module according to claim 15, wherein the third cover member is a portion formed by bending in a direction perpendicular to one surface located on both sides of the module frame.

17. The battery module according to claim 1, wherein the heat insulating member includes silicon (Si).

18. The battery module according to claim 1, wherein the cover member includes an insulating material made of mica or an inorganic material.

19. A battery pack comprising a battery module according to any one of claims 1 to 18.

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