Battery module and battery pack including same

Abstract

The invention provides a battery module and a battery pack including the same. A battery module according to an exemplary embodiment of the present invention comprises: a battery cell stack including one or more battery cells; and a module frame for accommodating the battery cell stack, in which the module frame includes, in at least one surface, a pattern structure in which a plurality of holes are formed in a repeating shape, and the pattern structure is a truss structure in which the shape of the holes is triangular.

Description

[0001] This application is a divisional application of LG New Energy Corporation's invention patent application (filed on October 14, 2021, application number 202111198472.9, entitled "Battery Module and Battery Pack Including the Battery Module"). Technical Field

[0002] The present invention relates to a battery module and a battery pack including the battery module, and more particularly to a battery module and a battery pack including the battery module that can simultaneously improve the safety of the battery module and maintain the rigidity of the battery module. Background Technology

[0003] In modern society, with the widespread use of portable devices such as mobile phones, laptops, portable camcorders, and digital cameras, the development of technologies related to mobile devices has become increasingly active. Furthermore, rechargeable secondary batteries are a solution to air pollution from existing gasoline vehicles using fossil fuels and are used as a power source for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs), leading to an increased demand for the development of secondary batteries.

[0004] Currently, commercially available rechargeable batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium rechargeable batteries. Among them, compared with nickel-based rechargeable batteries, lithium rechargeable batteries have the advantages of very small memory effect, free charging and discharging, very low self-discharge rate, and very high energy density.

[0005] Lithium-ion secondary batteries primarily use lithium-based oxides and carbon materials as the positive and negative electrode active materials, respectively. A lithium-ion secondary battery comprises an electrode assembly and an external material. Positive and negative electrode plates, each coated with a positive electrode active material, are sandwiched between a separator within the electrode assembly. The external material, the battery casing, seals and contains the electrode assembly and the electrolyte together.

[0006] Generally, based on the shape of the external material, lithium secondary batteries can be divided into can-type secondary batteries and pouch-type secondary batteries. In can-type secondary batteries, the electrode assembly is embedded in a metal can, while in pouch-type secondary batteries, the electrode assembly is embedded in a pouch made of aluminum laminate.

[0007] In the case of secondary batteries for small devices, two or three battery cells are used. However, in the case of secondary batteries for medium and large devices (such as automobiles), battery modules in which multiple battery cells are electrically connected are used. Multiple battery cells are connected in series or parallel to form a battery assembly, giving the battery module improved capacity and output. Furthermore, one or more battery modules can be installed with various control and protection systems, such as a battery management system (BMS) and a cooling system, to form a battery pack.

[0008] When configuring a battery pack by connecting multiple battery cells in series or parallel, the general approach is to first configure a battery module consisting of at least one battery cell, and then configure the battery pack by adding other components using at least one battery module. The number of battery modules included in the battery pack, or the number of battery cells included in a battery module, can be set differently depending on the required output voltage or charge / discharge capacity.

[0009] Because it is desirable for medium and large battery modules to be manufactured with lightweight and thin structures, prismatic cells, pouch cells, and other battery cells that can be stacked in a highly integrated manner and have a small weight-to-capacity ratio are mainly used as battery cells in medium and large battery modules. At the same time, in order to protect the battery cell stack from external shocks, heat, or vibration, the battery module may include a frame member that houses the battery cell stack in an internal space and covers the top, bottom, left, and right surfaces of the battery cell stack.

[0010] Because the multiple battery cells included within the battery module have a stacked structure, a venting structure can be used to quickly dissipate heat and flame to the outside when ignition occurs within the battery module cells. However, this also presents the problem of foreign matter entering the venting holes, and the application of venting holes reduces the rigidity of the battery module.

[0011] The information disclosed in this background section is only intended to enhance the understanding of the background of the present invention, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0012] The present invention aims to provide a battery module and a battery pack including the battery module, wherein the battery module can effectively exhaust heat and flame to the outside when ignition occurs in the battery module, maintain the rigidity of the battery module, prevent the inflow of foreign objects, and prevent the rapid spread of flame.

[0013] However, the objectives to be addressed in the exemplary embodiments of the present invention are not limited to the above objectives, and various extensions can be made within the scope of the technical spirit encompassed by the present invention.

[0014] An exemplary embodiment of the present invention provides a battery module comprising: a battery cell stack including one or more battery cells; and a module frame for accommodating the battery cell stack, wherein the module frame includes a patterned structure in at least one surface, wherein a plurality of holes are formed in the patterned structure in a repeating shape, and the battery module further includes a fire extinguishing agent sheet disposed between the patterned structure and the battery cell stack.

[0015] The pattern structure can be a truss structure in which the hole is triangular in shape.

[0016] The module frame can be made of metal.

[0017] The battery module may further include: a pair of end plates disposed at both ends in the longitudinal direction of the battery cell stack, wherein the module frame may be formed corresponding to the four surfaces of the battery cell stack not covered by the pair of end plates, and the pattern structure may not be disposed on the surface of the four surfaces corresponding to the bottom surface of the battery cell stack.

[0018] The pattern structure can be set on a surface of the module frame corresponding to the upper surface of the battery cell stack.

[0019] The pattern structure can be set on the entire surface of the module frame corresponding to the upper surface of the battery cell stack.

[0020] The pattern structure may be provided only on a portion of one surface of the module frame corresponding to the upper surface of the battery cell stack.

[0021] The pattern structure can be set on one surface of the module frame corresponding to either side of the battery cell stack.

[0022] The extinguishing agent tablets may include one or more selected from inorganic carbonates, inorganic phosphates, and inorganic sulfates.

[0023] Another exemplary embodiment of the present invention provides a battery pack including: the at least one battery module, and a battery pack housing configured to encapsulate the at least one battery module.

[0024] According to an exemplary embodiment of the present invention, when ignition occurs in the battery module, heat and flame can be effectively discharged to the outside, maintaining the rigidity of the battery module, preventing the introduction of foreign objects, and preventing the flame from spreading rapidly. Attached Figure Description

[0025] Figure 1 This is a perspective view of a battery module according to an exemplary embodiment of the present invention.

[0026] Figure 2 yes Figure 1 An exploded 3D view of the battery module.

[0027] Figure 3 It shows the view from above. Figure 1 A diagram of the battery module.

[0028] Figure 4 This is an exploded perspective view of a battery module according to another exemplary embodiment of the present invention.

[0029] Figure 5 This is an exploded perspective view of a battery module according to yet another exemplary embodiment of the present invention.

[0030] The reference numerals in the attached figures are explained as follows:

[0031] 100: Battery Module

[0032] 200: Module Framework

[0033] 210: Pattern Structure

[0034] 210a: Hole

[0035] 300: End plate

[0036] 400: Battery cell stack

[0037] 600: Fire extinguishing agent tablets Detailed Implementation

[0038] The invention will be described more fully below with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated.

[0039] However, the present invention can be implemented in various ways and is not limited to the following embodiments.

[0040] Therefore, the accompanying drawings and descriptions should be considered illustrative rather than restrictive in nature. Throughout the specification, the same reference numerals denote the same elements.

[0041] Furthermore, the dimensions and thicknesses of the structures shown in the accompanying drawings are arbitrarily illustrated for understanding and ease of explanation, but the invention is not limited thereto. In the drawings, the thicknesses of layers, films, panels, regions, etc., are enlarged for clarity. In the drawings, the thicknesses of some layers and regions are enlarged for understanding and ease of description.

[0042] Furthermore, it should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element, or there may be intermediate elements present. Conversely, when an element is referred to as being "directly on" another element, there are no intermediate elements present. Additionally, in this specification, the term "on" means positioned above or below the object portion, but does not substantially mean positioned on the upper side of the object portion based on the direction of gravity.

[0043] Furthermore, unless explicitly stated otherwise, the words “including” and variations such as “contains” or “comprising” will be understood to imply inclusion of the stated element, but not exclusion of any other element.

[0044] Figure 1 This is a perspective view of a battery module according to an exemplary embodiment of the present invention. Figure 2 yes Figure 1 An exploded 3D view of the battery module, and Figure 3 It shows the view from above. Figure 1 A diagram of the battery module.

[0045] See Figures 1 to 3 According to an exemplary embodiment of the present invention, a battery module 100 includes: a battery cell stack 400, which includes one or more battery cells; a module frame 200 for receiving the battery cell stack 400; and a pair of end plates 300, which are positioned at both ends in the longitudinal direction of the battery cell stack 400 and connected to an opening in the module frame 200.

[0046] Battery cell stack 400 is an assembly of a secondary battery comprising a plurality of battery cells 112. Battery cell stack 400 may include a plurality of battery cells 112, and each battery cell includes electrode leads. Battery cells 112 may be plate-shaped or pouch-type battery cells, but are not limited thereto. Electrode leads may be positive or negative electrode leads, and the ends of the electrode leads of each battery cell 112 may be bent in one direction, and thus may contact the ends of the electrode leads of another adjacent battery cell 112. The two contacting electrode leads may be fixed together by welding or the like, thus electrically connecting the battery cells 112 within battery cell stack 400.

[0047] Furthermore, the busbar frame 500 housed in the module frame 200 can be disposed together with the battery cell stack 400. The busbar frame 500 may include an upper frame 510 positioned on the upper part of the battery cell stack 400, a front frame 520 positioned on the front surface of the battery cell stack 400, and a rear frame 530 positioned on the rear surface of the battery cell stack 400, and busbars 540 connected to the electrode leads of the battery cells constituting the battery cell stack 400 can be mounted to the front frame 520 and the rear frame 530.

[0048] Multiple battery cells 112 are vertically stacked such that the electrode leads are aligned in one direction to form a battery cell stack 400. The battery cell stack 400 is housed in a module frame 200, which includes at least one opening in the longitudinal direction of the battery cell stack 400. In this configuration, the electrode leads are extended through the openings to the outside of the module frame 200, and the extended electrode leads are respectively connected to the front frame 520 and the rear frame 530 of the busbar frame 500 for electrical connection with the mounted busbar 540. Here, the busbar frame 500 may be made of an insulating material, such as a non-conductive synthetic resin, and the busbar 540 may be made of a conductive metal material.

[0049] The battery module 100 may include a flexible printed circuit board (FPCB) (not shown) that extends in the longitudinal direction of the module frame 200 and is mounted in the upper part of the battery cell stack 400 to sense the battery cells 112. Furthermore, the battery module 100 may include various electronic components, such as an internal circuit board (ICB) and a battery management system (BMS). Electronic components such as the ICB and BMS boards may be electrically connected to multiple battery cells 112.

[0050] In the battery module 100 according to this exemplary embodiment, the module frame 200 can be formed to cover four surfaces of the battery cell stack 400, excluding the two side ends. That is, in Figure 2 In this configuration, the battery cell stack 400 may have an upper surface and a bottom surface at its upper and lower parts respectively along the z-axis direction. The upper surface 200a of the module frame 200 may be located at a position corresponding to the upper surface of the battery cell stack 400, and the bottom surface 200b of the module frame 200 may be located at a position corresponding to the bottom surface of the battery cell stack 400. A pair of side surfaces 200c corresponding to the side surfaces of the battery cell stack 400 may be located between the upper surface 200a and the bottom surface 200b. In this configuration, the module frame 200 may have the following characteristics: Figure 2 The rectangular tube shape shown is not limited to this, and the module frame 200 can also have a structure in which a U-shaped frame formed by the bottom surface 200b and a pair of side surfaces 200c perpendicularly connected to both sides of the bottom surface 200b is connected to an upper plate connected to the U-shaped frame to form an upper surface 200a. Furthermore, the module frame 200 can have a structure in which an inverted U-shaped frame formed by the upper surface 200a and the two side surfaces 200c is connected to a lower plate forming the bottom surface 200b, but this is not particularly limited. Additionally, although not shown, a curved surface corresponding to the shape of the lower portion of the battery cell 112 included in the battery cell stack 400 is formed inside the bottom surface 200b for which the battery cell stack 400 is housed, thereby providing more stable support for the battery cell 112. Furthermore, although not shown, a thermally conductive resin layer can also be formed between the battery cell stack 400 and the bottom surface 200b to dissipate heat generated from the battery cell 112.

[0051] The module frame 200 can be made of a metallic material. The metallic material can be one or more selected from steel and aluminum. End plates 300 are respectively connected to the two open ends of the module frame 200. The end plates 300 can be made of a metallic material, thus possessing rigidity to protect their internal components, such as the battery cell stack 400 and the busbar frame 500. The end plates 300, made of a metallic material, can be connected to the module frame 200, which is also made of a metallic material, by methods such as welding.

[0052] Simultaneously, the module frame 200 may include a patterned structure 210 formed of holes 210a with repeating shapes on at least one surface. By including the patterned structure 210 in the module frame 200 made of metallic material, gas can easily escape through the holes 210a of the patterned structure 210 in the event of a problem such as ignition inside the battery module 100. That is, the holes 210a of the patterned structure 210 can serve as vents. Furthermore, although a patterned structure 210 including multiple holes 210a is formed, the holes 210a are formed with repeating shapes, thereby maintaining the rigidity of the battery module 100. In particular, the patterned structure 210 may have a truss structure, wherein the holes 210a have a triangular shape. That is, as shown... Figure 3 As shown, when the pattern structure 210 has a truss structure in which beams made of metal are connected to form triangular holes 210a, the shape of the pattern structure 210 is not easily changed even when external forces are applied, thus maintaining rigidity. Therefore, one surface of the module frame 200 (the upper surface 200a in this exemplary embodiment) has an opening to serve as a vent, while the rigidity of the module frame 200 can be maintained by the pattern structure 210.

[0053] In this configuration, the extinguishing agent plate 600 is disposed between the pattern structure 210 and the battery cell stack 400. By disposing of the extinguishing agent plate 600, foreign objects can be prevented from being introduced from the outside through the holes 210a of the pattern structure 210. Furthermore, when ignition or other events occur inside the battery module 100, carbon dioxide gas is released under thermal runaway conditions through the extinguishing agent contained in the extinguishing agent plate 600, giving the battery module 100 a self-extinguishing function capable of suppressing the combustion reaction. This can weaken or eliminate the flame, thereby delaying the spread of the flame to the surrounding environment. The extinguishing agent can be included in the extinguishing agent plate 600, and as the extinguishing agent, one or more selected from the group consisting of inorganic carbonates, inorganic phosphates, and inorganic sulfates can be used, but this is not particularly limited.

[0054] As described above, according to an exemplary embodiment of the present invention, the battery module includes a patterned structure 210 in at least one surface of the module frame 200, wherein holes 210a are formed in a repeating shape, and the battery module includes a fire extinguishing agent sheet 600 disposed between the patterned structure 210 and the battery cell stack 400, such that even if the battery module 100 includes a plurality of holes 210a that serve as vents when ignition occurs inside the battery module 100, the rigidity of the module frame 200 can be maintained while preventing foreign objects from being introduced from the outside. Furthermore, the fire extinguishing agent sheet 600 can delay the flame propagation speed, thereby improving the safety of the battery module 100.

[0055] Next, we will refer to Figure 4 and Figure 5Another exemplary implementation and yet another exemplary implementation are described.

[0056] Figure 4 This is an exploded perspective view of a battery module according to another exemplary embodiment of the present invention, and Figure 5 This is an exploded perspective view of a battery module according to yet another exemplary embodiment of the present invention.

[0057] like Figure 4 As shown, in another exemplary embodiment of the invention, a patterned structure 210 formed by repeating holes 210a is formed in either side surface 200c of the module frame 200. In this case, the fire extinguishing agent sheet 600 can be disposed between the side surface 200c in which the patterned structure 210 is formed and the battery cell stack 400. Even when the patterned structure 210 is formed in the side surface 200c as described above, the rigidity of the module frame 200 can be maintained, and at the same time, when ignition occurs inside the battery module 100, the holes 210a contained in the patterned structure 210 can be used as vents. Furthermore, Figure 4 The pattern structure 210 is shown to be formed only in the side surface 200c, but the pattern structure 210 can be formed in both the side surface 200c and the top surface 200a, and the pattern structure 210 can be formed in both side surfaces 200c. However, in the case of mounting the battery module 100 to the bottom surface 200b of the battery pack or device, the bottom surface 200b is not suitable for venting flames or the like to the outside when ignition occurs. Therefore, it is preferable that the pattern structure 210 is formed in the portion other than the bottom surface 200b.

[0058] In addition, such as Figure 5 As shown, in another exemplary embodiment of the present invention, the pattern structure 210 formed by the repeating shape of the holes 210a is formed only in a portion of the upper surface 200a of the module frame 200. That is, as Figure 5 As shown, the pattern structure 210 and the portions therein without a pattern structure can be repeated in stripes, and conversely, the pattern structure 210 can be applied only to the central portion of the upper surface 200a. With this construction, the rigidity of the module frame 200 can be maintained, while the holes 210a included in the pattern structure 210 can serve as vents when ignition occurs inside the battery module 100. Furthermore, in this configuration, the extinguishing agent sheet 600 can be disposed between the upper surface 200a and the battery cell stack 400, and... Figure 5 The fire extinguishing agent sheet 600 is shown to correspond to the entire upper surface 200a, but the invention is not limited thereto and can be suitably applied to any location that can cover all the holes 210a included in the pattern structure 210.

[0059] As described above, according to an exemplary embodiment of the present invention, the battery module includes a pattern structure 210 formed by repeating the shape of holes 210a in at least one surface of the module frame 200, and the battery module includes a fire extinguishing agent sheet 600 disposed between the pattern structure 210 and the battery cell stack 400, thereby maintaining the rigidity of the module frame 200, and simultaneously, when ignition occurs inside the battery module 100, the holes 210a included in the pattern structure 210 can be used as vents, thereby improving the safety of the battery module 100. Furthermore, the fire extinguishing agent sheet 600 can delay the flame propagation speed, thereby further improving the safety of the battery module 100.

[0060] Meanwhile, the battery module according to an exemplary embodiment of the present invention can be encapsulated in one or more battery pack housings to form a battery pack.

[0061] The aforementioned battery module and battery pack including the battery module can be applied to various devices. As such devices, they can be applied to transportation devices such as electric bicycles, electric vehicles, and hybrid vehicles; however, the invention is not limited thereto, and it is applicable to various devices capable of using the battery module and battery pack including the battery module, which also fall within the scope of this invention.

[0062] Although exemplary embodiments of the invention have been described in detail, the scope of the invention is not limited to these embodiments. Various changes and modifications made by those skilled in the art using the basic concepts of the invention as defined in the appended claims will be interpreted as falling within the scope of the invention.

Claims

1. A battery module, the battery module comprising: A battery cell stack, the battery cell stack comprising one or more battery cells; as well as A modular framework for accommodating the battery cell stack. The module frame includes a patterned structure on at least one surface, in which a plurality of holes are formed in a repeating shape, and the patterned structure is a truss structure in which the holes are triangular in shape.

2. The battery module according to claim 1, wherein: The module frame is made of metal.

3. The battery module according to claim 1, wherein, The battery module further includes: A pair of end plates, the pair of end plates being disposed at both ends in the longitudinal direction of the battery cell stack. The module frame is formed corresponding to the four surfaces of the battery cell stack that are not covered by the pair of end plates, and The pattern structure is not disposed on the surface of the four surfaces corresponding to the bottom surface of the battery cell stack.

4. The battery module according to claim 3, wherein: The pattern structure is disposed on a surface of the module frame corresponding to the upper surface of the battery cell stack.

5. The battery module according to claim 4, wherein: The pattern structure is disposed on the entire surface of the module frame corresponding to the upper surface of the battery cell stack.

6. The battery module according to claim 4, wherein: The pattern structure is only provided on a portion of one surface of the module frame corresponding to the upper surface of the battery cell stack.

7. The battery module according to claim 3, wherein: The pattern structure is disposed on one surface of the module frame corresponding to either side of the battery cell stack.

8. The battery module according to claim 1, wherein, The battery module also includes a fire extinguishing agent sheet disposed between the patterned structure and the battery cell stack. The extinguishing agent tablets include one or more selected from inorganic carbonates, inorganic phosphates, and inorganic sulfates.

9. The battery module according to claim 8, wherein: The extinguishing agent pad prevents foreign objects from being introduced from the outside through the holes in the patterned structure.

10. A battery pack, the battery pack comprising: At least one battery module, said battery module being the battery module according to any one of claims 1 to 9; as well as A battery pack housing configured to enclose the at least one battery module.

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