Battery module and battery pack containing the same for thermal runaway delay

Abstract

A battery module for thermal runaway delay according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module case for accommodating the battery cell stack, and an end plate disposed on one side of the module case, wherein at least a portion of the end plate is coated with a flame-retardant paint.

Description

[Technical Field]

[0001] The present invention relates to a battery module and a battery pack including the same, and more particularly, to a battery module for delaying thermal runaway and a battery pack including the same. [Background Art]

[0002] Unlike non-rechargeable primary batteries, secondary batteries refer to batteries that can be charged and discharged, and are applied not only to portable devices, but also to electric vehicles (EVs) driven by electric drive sources, hybrid electric vehicles (HEVs), and the like.

[0003] Currently widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and the like. The operating voltage of such a unit secondary battery cell, that is, a unit battery cell, is about 2.5V to 4.6V. Therefore, when a higher output voltage is required, a plurality of battery cells are connected in series to form a battery pack. In addition, depending on the charge-discharge capacity required for the battery pack, a plurality of battery cells may be connected in parallel to form a battery pack. Therefore, the number of battery cells included in the battery pack can be variously set according to the required output voltage or charge-discharge capacity.

[0004] When forming a battery pack by connecting a plurality of battery cells in series / parallel, it is common to first form a battery module including at least one battery cell, preferably a plurality of battery cells, then use at least one such battery module and add other components to form the battery pack. Here, the battery module refers to a component in which a plurality of battery cells are connected in series or parallel, and the battery pack refers to a component in which a plurality of battery modules are connected in series or parallel to increase capacity, output, and the like.

[0005] However, if overcharging occurs, such battery packs can explode or catch fire due to swelling of the battery module, and such explosions and fires can pose a greater risk, potentially leading to loss of life.

[0006] During thermal runaway of a battery pack, gases and particles generated from the module can cause external short circuits in adjacent modules, which can accelerate the thermal transition rate. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The present invention aims to solve the aforementioned problems and to provide a battery module for delaying thermal runaway and a battery pack including the same. [Means for solving the problem]

[0008] A battery module for delaying thermal runaway according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module case for housing the battery cell stack, and an end plate disposed on one side of the module case, wherein at least a portion of the end plate is coated with flame-retardant paint.

[0009] Furthermore, the end plate includes a terminal opening.

[0010] Furthermore, the flame-retardant paint is applied to the end plate around the terminal opening.

[0011] Furthermore, the battery module for thermal runaway delay further includes a terminal busbar, one end of which is exposed through the terminal opening.

[0012] The system further includes a busbar frame positioned on one side of the battery cell stack.

[0013] Furthermore, the terminal busbar is positioned on the busbar frame.

[0014] The system further includes an insulating cover positioned on the outside of the busbar frame.

[0015] Furthermore, the insulating cover includes an opening through which the terminal busbar is exposed.

[0016] Furthermore, the flame-retardant paint is applied to the front surface of the end plate.

[0017] A battery module for delaying thermal runaway according to one embodiment of the present invention includes a battery cell stack in which a plurality of battery cells are stacked, a module case for housing the battery cell stack, and an end plate disposed on one side of the module case, wherein at least a portion of the end plate is coated with heat-resistant paint.

[0018] Furthermore, the heat-resistant paint is applied to the end plate around the terminal opening.

[0019] Furthermore, the heat-resistant paint is applied to the front surface of the end plate. [Effects of the Invention]

[0020] A battery module and a battery pack containing the same according to one embodiment of the present invention have the effect of delaying or preventing the occurrence of external short circuits in adjacent modules caused by gases and particles generated in the thermally runaway battery module, thereby delaying thermal runaway. [Brief explanation of the drawing]

[0021] [Figure 1] This is a perspective view of a battery module according to one embodiment of the present invention. [Figure 2]It is an exploded perspective view of a battery module according to an embodiment of the present invention. [Figure 3] It is a perspective view of a battery cell according to an embodiment of the present invention. [Figure 4] It is a perspective view of a terminal bus bar according to an embodiment of the present invention. [Figure 5] It is a perspective view of an insulating cover and an end plate according to an embodiment of the present invention. [Figure 6] It is a perspective view of an end plate according to an embodiment of the present invention. [Figure 7] It is a front view of an end plate according to an embodiment of the present invention. [Figure 8] It is a perspective view of an end plate according to another embodiment of the present invention. Description of Embodiments

[0022] The advantages and features of the present invention, and the method for achieving the same, will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be embodied in various different forms. The present embodiments are provided merely to complete the disclosure of the present invention and to fully inform those skilled in the art to which the present invention pertains of the scope of the invention, and the present invention is defined solely by the claims. Accordingly, in some embodiments, well-known process steps, well-known element structures and well-known techniques are not specifically described in order to avoid ambiguous interpretation of the present invention. Like reference numerals refer to like elements throughout the specification.

[0023] In drawings, thicknesses may be exaggerated to clearly represent multiple layers and regions. Similar parts are given the same drawing reference numerals throughout the specification. When a layer, film, region, plate, or other part is said to be "on top" of another part, this includes not only when it is "immediately above" the other part, but also when there is another part in between. Conversely, when a part is said to be "immediately above" another part, it means there is no other part in between. Similarly, when a layer, film, region, plate, or other part is said to be "below" another part, this includes not only when it is "immediately below" the other part, but also when there is another part in between. Conversely, when a part is said to be "immediately below" another part, it means there is no other part in between.

[0024] A battery module 1000 according to one embodiment of the present invention will be described in detail with reference to the drawings.

[0025] Figure 1 is a perspective view of the battery module according to the present invention, Figure 2 is an exploded perspective view of the battery module according to the present invention, Figure 3 is a perspective view of the battery cell according to the present invention, Figure 4 is a perspective view of the terminal busbar according to the present invention, Figure 5 is a perspective view of the insulating cover and end plate according to the present invention, Figure 6 is a perspective view of the end plate according to one embodiment of the present invention, Figure 7 is a front view of the end plate according to one embodiment of the present invention, and Figure 8 is a perspective view of the end plate according to another embodiment.

[0026] A battery module 1000 according to one embodiment of the present invention may include a battery cell stack 100 in which a plurality of battery cells 110 are stacked, a module case 200 that houses the battery cell stack 100, a busbar frame 300 located on one side and / or the other side of the battery cell stack 100, an insulating cover 500 disposed on the outside of the busbar frame 300, and an end plate 400 disposed on the outside of the insulating cover 500.

[0027] The battery cell stack 100 is constructed by stacking a plurality of battery cells 110 along one direction, and the plurality of battery cells 110 may be electrically connected. The direction in which the plurality of battery cells 110 are stacked may be the X-axis direction (or -X-axis direction) in Figure 2.

[0028] The direction from the front to the rear of the battery cell stack 100, or the opposite direction, can be defined as the length direction of the battery cell stack 100, and may be the Y-axis direction on the drawing. Furthermore, the direction from the top to the bottom of the battery cell stack 100, or the opposite direction, can be defined as the width direction of the battery cell stack 100, and may be the Z-axis direction on the drawing.

[0029] The longitudinal direction of the battery cell stack 100 may be substantially the same as the longitudinal direction of the battery cells 110. The electrode leads 111 and 112 of the battery cells 110 may be located on the front and rear surfaces of the battery cell stack 100, and the busbars 310 and 320 of the battery module 1000 may be positioned close to the front and rear surfaces of the battery cell stack 100 to facilitate electrical connections with the electrode leads 111 and 112.

[0030] The battery cell 110 may be provided as a pouch-type battery cell, which maximizes the number of layers per unit area. However, the battery cell 110 does not necessarily have to be provided as a pouch type, and can also be provided in prismatic, cylindrical, or other various forms.

[0031] The battery cell 110, provided in a pouch, may include an electrode assembly and a cell case 115 that houses the electrode assembly (see Figure 3).

[0032] The cell case 115 of the battery cell 110 is for housing the electrode assembly and may be a pouch-type cell case 115. The cell case 115 includes a lower case and an upper case that covers the lower case, and the upper case and lower case may be integrated. Also, as shown in Figure 3, the connecting portion of the upper case and lower case may be folded and foldable. Furthermore, as shown in the figure, the upper case may completely cover the lower case, and a sealing portion 114 may be formed around the periphery.

[0033] Both the upper and lower cases may be laminate structures including an internal coating layer, a metal layer, and an external coating layer. The internal coating layer is located inside the cell case 115 relative to the metal layer and is in direct contact with the electrode assembly, so it must have insulating and electrolytic resistance properties. Furthermore, for sealing to the outside, it is required to have sealing properties, that is, the sealing portions where the internal layers are heat-bonded together must have excellent thermal bonding strength. The metal layer is located between the internal coating layer and the external coating layer and acts as a barrier layer to prevent moisture and various gases from penetrating into the inside of the battery from the outside. A preferred material for the metal layer in contact with the internal coating layer is a thin film of aluminum (Al) which is lightweight but has excellent moldability. The external coating layer is located outside the cell case 115 relative to the metal layer, and such an external coating layer can be made of a heat-resistant polymer with excellent tensile strength, moisture permeability prevention, and air permeability prevention properties so as to protect the electrode assembly while ensuring heat resistance and chemical resistance. For example, nylon or polyethylene terephthalate can be used.

[0034] The upper case and the lower case may each have a housing groove 116, and the electrode assembly may be housed in the housing groove 116 of the upper case and the lower case.

[0035] The electrode assembly housed in the cell case 115 may be one selected from the group consisting of a jelly roll type electrode assembly having a structure in which a separation membrane is interposed between a positive electrode and a negative electrode that are both long sheets and wound together; a stack type electrode assembly consisting of unit cells having a structure in which rectangular positive and negative electrodes are stacked with a separation membrane in between; a stack folding type electrode assembly in which the unit cells are wound with a long separation film; and a lamination stack type electrode assembly in which the unit cells are stacked with a separation membrane in between and adhere to each other.

[0036] The electrode assembly may also include two electrode tabs and two electrode leads 111 and 112 connected to these electrode tabs via welded joints.

[0037] One of the two electrode leads 111, 112 may be a positive lead connected to a positive tab, and the other electrode lead 111, 112 may be a negative lead connected to a negative tab.

[0038] A lead film 113 may be attached to each of the electrode leads 111 and 112. The lead film 113 attached to the electrode leads 111 and 112 is located between the electrode leads 111 and 112 and the cell case 115, preventing short circuits from occurring between the electrode leads 111 and 112 and the cell case 115, improving sealing and preventing leakage of electrolyte.

[0039] Although the two electrode leads 111 and 112 are shown positioned on both sides of the electrode assembly, they may be positioned on only one side of the electrode assembly depending on the arrangement of the electrode tabs.

[0040] The module case 200 is intended to protect the battery cell stack 100 and the electrical components connected thereto from external physical shocks, and the module case 200 can house the battery cell stack 100 and the electrical components connected thereto in its internal space.

[0041] The structure of the module case 200 is diverse, and as one example, the module case 200 may have a monoframe structure. Here, the monoframe may be in the form of a metal sheet material in which the top surface, bottom surface, and both sides are integrated. The monoframe can be manufactured by extrusion molding. As another example, the structure of the module case 200 may be a structure in which a U-shaped frame and an upper plate (top surface 201) are joined together. In the case of a structure in which a U-shaped frame and an upper plate are joined together, the structure of the module case 200 can be formed by joining the upper plate to the upper side of a U-shaped frame made of a metal sheet material in which the bottom surface and both sides are joined or integrated, and each frame or plate can be manufactured by press molding. Furthermore, in addition to the monoframe or U-shaped frame, the structure of the module case 200 can also be provided as an L-shaped frame structure, and can be provided as a variety of structures not described in the examples above.

[0042] The structure of the module case 200 can be provided in an open form along the length of the battery cell stack 100. The front and rear surfaces of the battery cell stack 100 do not need to be shielded by the module case 200. The electrode leads 111 and 112 of the battery cells 110 do not need to be shielded by the module case 200. The front and rear surfaces of the battery cell stack 100 can be shielded by a busbar frame 300, end plate 400, or busbars 310, 320, etc., which will be described later, thereby protecting the front and rear surfaces of the battery cell stack 100 from external physical impacts, etc.

[0043] A compression pad 150 may be placed between the battery cell stack 100 and one side of the inner surface of the module case 200.

[0044] The compression pad 150 may be positioned in the battery cell stack 100 so as to face the outermost battery cell 110 of the battery cell stack 100 in the X-axis direction as shown in the drawing.

[0045] Furthermore, although not shown in the figures, a thermally conductive resin may be injected between the battery cell stack 100 and the inner surface of the module case 200, and a thermally conductive resin layer (not shown) may be formed between the battery cell stack 100 and one of the inner surfaces of the module case 200 by the injected thermally conductive resin. Here, the thermally conductive resin layer can be located on the Z-axis of the battery cell stack 100, and may be formed between the thermally conductive resin battery cell stack 100 and the bottom surface of the module case 200 located on the -Z-axis.

[0046] The busbar frame 300 is positioned on one surface of the battery cell stack 100, covering one surface of the battery cell stack 100 and guiding the connection between the battery cell stack 100 and external equipment. Specifically, as shown in the figure, the busbar frame 300 may be positioned on the front or rear surface of the battery cell stack 100, or on the top, bottom, or side surface. At least one of the busbars 310, 320, and module connectors may be mounted on the busbar frame 300. As shown in Figure 3, one surface of the busbar frame 300 may be connected to one or the other surface of the battery cell stack 100, and the other surface of the busbar frame 300 may be connected to the busbars 310, 320.

[0047] The busbar frame 300 may include an electrically insulating material. The busbar frame 300 can restrict the busbars 310 and 320 from contacting other parts of the battery cell 110 other than the parts joined to the electrode leads 111 and 112, thereby preventing electrical short circuits.

[0048] The busbar frame 300 may be located on one side and the other side of the battery cell stack 100, respectively.

[0049] Busbars 310 and 320 are mounted on the busbar seating portion 340 on one surface of the busbar frame 300 and may be used to electrically connect the battery cell stack 100 or battery cells 110 to external equipment circuits. Multiple busbars 310 and 320 may be arranged and positioned between the battery cell stack 100 or busbar frame 300 and the end plate 400 to protect them from external impacts and minimize deterioration of durability due to external moisture.

[0050] The busbars 310 and 320 may be electrically connected to the battery cell stack 100 via the electrode leads 111 and 112 of the battery cell 110.

[0051] Specifically, the electrode leads 111 and 112 of the battery cell 110 may pass through lead slits formed in the busbar frame 300, then bend and connect to the busbars 310 and 320. As shown in Figure 8, the electrode leads 111 and 112 of the battery cell 110 may be connected to both sides of the busbars 310 and 320. The electrode lead 111 connected to one side of the busbars 310 and 320 may be a positive electrode lead, and the electrode lead 112 connected to the other side of the busbars 310 and 320 may be a negative electrode lead.

[0052] The busbars 310 and 320 allow the battery cells 110 constituting the battery cell stack 100 to be connected in series or in parallel.

[0053] The busbars 310 and 320 may include a terminal busbar 320 for electrically connecting one battery module 100 to another battery module 100. To connect to another battery module 100, at least a portion of the terminal busbar 320 is exposed to the outside of the end plate 400, which may have a terminal opening 410 for this purpose.

[0054] The terminal busbar 320 may have one end (second portion 322) exposed to the outside of the module 1000 through the opening 510 of the insulating cover 500 and the terminal opening 410 of the end plate 400.

[0055] As shown in Figure 4, the terminal busbar 320 may include a first portion 321 connected to the electrode leads 111 and 112 of the battery cell 110, and a second portion 322 exposed to the outside through the terminal opening 410. The terminal busbar 320 may further include a bending portion 323 formed between the first portion 321 and the second portion 322.

[0056] In the terminal bus bar 320, the first portion 321 is connected to the second portion 322 via a bending portion 323, and one face of the first portion 321 and one face of the second portion 322 may be perpendicular to each other. That is, by forming a bent bending portion 323 in the terminal bus bar 320, the second portion 322 may protrude and seat on the seating portion 530 of the insulating cover 500, and the second portion 322 may be electrically connected to the pack bus bar 1100. A coupling hole 322a is formed in the second portion 322 that constitutes one end of the terminal bus bar 320, and the second portion 322 of the terminal bus bar 320 is fixed by a fixing pin 550 inserted into this coupling hole 322a.

[0057] Furthermore, an insulating cover 500 for electrical insulation may be positioned between the busbar frame 300 and the end plate 400. That is, the busbar frame 300, insulating cover 500, and end plate 400 may be positioned sequentially outward from the battery cell stack 100. Similar to the end plate 400, the busbar frame 300 and insulating cover 500 may each be composed of multiple units.

[0058] The insulating cover 500 may include an electrically insulating material and can prevent the busbars 310 and 320 from coming into contact with the end plate 400.

[0059] The insulating cover 500 may include openings 510 and seating portions 530. The openings 510 are located on both sides of the upper part of the insulating cover 500, and one end (second portion 322) of the terminal bus bar 320 may be exposed through the openings 510.

[0060] Furthermore, a connector opening may be located between the openings 510 on both sides of the insulating cover 500, through which the module connector may be exposed to the outside.

[0061] The insulating cover 500 is located on the inner surface of the end plate 400 and can be in close contact with the inner surface of the end plate 400, but is not necessarily limited to this.

[0062] As described above, one end (second portion 322) of the terminal bus bar 320 may be exposed through the opening 510, and this exposed end (second portion 322) of the terminal bus bar 320 may be seated on the seating portion 530. Therefore, the seating portion 530 may be positioned adjacent to the opening 510 and on the upper outer surface.

[0063] The seating portion 530 can accommodate the second portion 322 of the terminal bus bar 320 on its upper surface, thereby forming a seating surface on the upper surface of the seating portion 530. Furthermore, as shown in Figure 5, the seating portion 530 may include a fixing portion 531 for securing the terminal bus bar 320.

[0064] The fixing member 531 can fix the second portion 322 of the terminal bus bar 320 and may include a fixing hole 531a.

[0065] A fixing pin (not shown) may be inserted into the fixing hole 531a. The second portion 322 of the terminal bus bar 320 can be fixed to the insulating cover 500 by being fixed by a fixing pin (not shown) inserted into a coupling hole 322a formed in the second portion 322 of the terminal bus bar 320 and coupled to the fixing hole 531a.

[0066] Therefore, the second portion 322 of the terminal bus bar 320 sits on the seating portion 530 of the insulating cover 500, and the second portion 322 sits on and contacts the fixing member 531 positioned on the seating portion 530.

[0067] Furthermore, a terminal cover portion (not shown) that covers one end (second portion 322) of the exposed terminal busbar 320 may be placed on the insulating cover 500.

[0068] The end plate 400 may also serve to protect the battery cell stack 100 and the electrical components connected thereto from external physical shocks by sealing the open surface of the module case 200. For this purpose, the end plate 400 can be manufactured from a material having a predetermined strength, and for example, the end plate 400 may include a metal such as aluminum or a plastic material.

[0069] Terminal openings 410 may be formed in the end plate 400. The terminal openings 410 are located on both sides of the end plate 400, and a portion of the insulating cover 500 and one end (second portion 322) of the terminal bus bar 320 may be exposed through the terminal openings 410.

[0070] Furthermore, a connector opening may be located between the terminal openings 410 on both sides of the end plate 400, and the module connector may be exposed to the outside through the connector opening.

[0071] The end plate 400 may be coupled to the module case 200 while covering the busbar frame 300 or busbars 310, 320 located on one surface of the battery cell stack 100. Each corner of the end plate 400 can be coupled to the corresponding corner of the module case 200 by methods such as welding, bolting, or hooking.

[0072] The end plates 400 may be positioned on one side and the other side of the module case 200, respectively, so as to cover both sides of the battery cell stack 100. In this embodiment, an example is shown in which the end plates 400 are positioned on the front and rear sides of the module case 200.

[0073] Furthermore, as shown in Figures 5 to 8, in one embodiment of the present invention, the end plate 400 may be coated with heat-resistant paint or flame-retardant paint 412 on at least a portion of it. Thus, the end plate 400 can include a flame-retardant coating layer (heat-resistant coating layer) on at least a portion of it.

[0074] The flame-retardant coating layer (heat-resistant coating layer) can be formed by applying heat-resistant paint or flame-retardant paint 412 to the end plate 400. The heat-resistant paint or flame-retardant paint 412 (shown in gray in the drawings) may be applied to the surrounding area 411 of the terminal opening 410, as shown in Figures 6 and 7, and thus the flame-retardant coating layer (heat-resistant coating layer) may be formed in the surrounding area 411 of the terminal opening 410. The heat-resistant paint or flame-retardant paint 412 may also be applied to the entire edge along the periphery of the terminal opening 410. For example, the surrounding area 411 of the terminal opening 410 on which the flame-retardant coating layer (heat-resistant coating layer) is formed may be within 10 mm or within 5 mm from the terminal opening 410.

[0075] The flame-retardant coating layer (heat-resistant coating layer) may be placed on the front portion 420 of the end plate 400, and the front portion 420 may include an upper vertical surface portion 412a, a horizontal surface portion 412b, and a lower vertical surface portion 412c, in the direction from top to bottom.

[0076] The flame-retardant coating layer (heat-resistant coating layer) may be formed on the upper vertical surface portion 412a, the horizontal surface portion 412b, and the upper edge 412d of the lower vertical surface portion 412c in the front portion 420.

[0077] In the front section 420, the upper vertical surface section 412a is positioned on the upper part of the front section 420 and may extend vertically in the height direction (Z-axis direction) of the battery module 1000. The flame-retardant coating layer (heat-resistant coating layer) may be formed over the entire upper vertical surface section 412a of the front section 420.

[0078] The horizontal surface portion 412b may be bent outward in the longitudinal direction (Y-axis direction) of the battery module 1000 at the lower end of the upper vertical surface portion 412a and extend horizontally, and may be positioned between the upper vertical surface portion 412a and the lower vertical surface portion 412c. The flame-retardant coating layer (heat-resistant coating layer) may be formed over the entire horizontal surface portion 412b.

[0079] In the front portion 420, the lower vertical surface portion 412c is located below the front portion 420 and may be bent downward at the front end of the horizontal surface portion 412b, extending vertically in the height direction (Z-axis direction) of the battery module 1000. The flame-retardant coating layer (heat-resistant coating layer) is formed on the upper edge 412d of the lower vertical surface portion 412c, and the width of the upper edge 412d on which the flame-retardant coating layer (heat-resistant coating layer) is formed may be 5 mm or less.

[0080] Furthermore, as shown in Figure 8, the heat-resistant or flame-retardant paint 412 may be applied not only to the area 411 surrounding the terminal opening 410 but also to the entire front part 420 of the end plate 400.

[0081] The end plate 400 may include a front portion 420 that is exposed to the outside of the module 1000 (or module case 200) and a rear portion 430 that faces inward from the module 1000 (or module case 200).

[0082] In the end plate 400, the front portion 420 is the part that faces outward from the module 1000 (or module case 200) and corresponds to the outer surface of the end plate 400. The front portion 420 includes an upper vertical surface portion 412a, a horizontal surface portion 412b, and a lower vertical surface portion 412c, extending from top to bottom.

[0083] In the end plate 400, the rear portion 430 is the part that faces inward into the module 1000 (or module case 200), and corresponds to the inner surface of the end plate 400, and may correspond to the opposite surface of the front portion 420.

[0084] The rear portion 430 may face the module case 200 or the insulating cover 500, or it may be coupled to the module case 200.

[0085] Here, as shown in Figure 8, heat-resistant paint or flame-retardant paint 412 may be applied to the front portion 420, excluding the rear portion 430 facing the insulating cover 500.

[0086] In this embodiment, silicone-based or epoxy-based paints can be used as the heat-resistant or flame-retardant paint 412.

[0087] In a battery pack, gas and particles generated in the battery module during thermal runaway cause an external short circuit in adjacent modules, accelerating the thermal transition rate.

[0088] In particular, the terminal busbar 320 is exposed in the area of ​​the terminal opening 410 of the end plate 400, and gas and particles can be released through this terminal opening 410 in the event of ignition.

[0089] In this embodiment, as described above, by applying heat-resistant paint or flame-retardant paint 412 to the area surrounding the terminal opening 410 or the front portion 420 of the end plate 400, the occurrence of an external short circuit in the adjacent module 1000 can be delayed or prevented, thereby delaying thermal runaway.

[0090] In this embodiment, the end plate 400 can be manufactured by sequentially performing the steps of die casting, shot blasting, painting, processing, and cleaning.

[0091] First, the die-casting stage is the stage in which molten metal is injected into a mold to obtain the end plate 400. For example, molten aluminum can be injected into the mold to obtain the end plate 400.

[0092] After die casting, the resulting end plate 400 can be subjected to shot blasting. The shot blasting step is for removing foreign matter such as sand remaining on the surface of the end plate 400 obtained after die casting, and can be done by projecting fine metallic or non-metallic particles onto the end plate 400 to remove the foreign matter.

[0093] After shot blasting, the painting stage can be carried out.

[0094] During the painting stage, as described above, heat-resistant paint or flame-retardant paint 412 can be applied to the surrounding area 411 of the terminal opening 410 or to the entire front part 420 of the end plate 400.

[0095] After that, the end plate 400 can be completed through processing and cleaning stages.

[0096] Table 1 below shows the results of an insulation performance evaluation test of the end plate 400 according to a preferred embodiment of the present invention.

[0097] As shown in Table 1, the insulation performance evaluation test showed no leakage current detected at both 0.5kV and 1kV voltages, indicating a pass (OK).

[0098] [Table 1]

[0099] As described above, one or more battery modules 1000 according to the present invention can form a battery pack, and electrical connections between the battery modules 1000 can be made via an interbus bar (not shown). The interbus bar is a member for connecting one battery module 1000 to another adjacent battery module 1000 or BDU (Battery Disconnect Unit), and may be connected to an exposed end (second portion 322) of a terminal bus bar 320. As an example, the interbus bar may be superimposed and connected on top of one end (second portion 322) of the terminal bus bar 320.

[0100] After one end of the interbusbar is superimposed on the second portion 322 of the terminal busbar 320, the fixing pins are sequentially inserted into the coupling holes of the interbusbar and the coupling holes 322a of the second portion 322 of the terminal busbar 320. Subsequently, the fixing pins are fixed to the fixing grooves 531a of the seating portion 530, thereby connecting the interbusbar to the terminal busbar 320.

[0101] Furthermore, the fixing pins allow the second portion 322 of the terminal busbar 320 to be secured to the insulating cover 500 together with the interbusbar.

[0102] The battery pack according to the present invention can house at least one or more battery modules 1000 inside the pack case and may include various control and protection systems such as a BMS (Battery Management System) and a cooling system.

[0103] The battery module 1000 and battery pack according to the present invention, configured in this manner, can be applied to a variety of devices. Specifically, they can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrid vehicles, as well as to energy storage systems (ESS), but are not limited to these, and can be applied to a variety of devices that can use secondary batteries.

[0104] Although the present invention has been described above based on preferred embodiments, it is not limited to the embodiments described above, and various modifications and alterations are possible by persons with ordinary skill in the art to which the present invention pertains, without departing from the spirit of the invention. [Industrial applicability]

[0105] The present invention provides a battery module and battery pack that delay or prevent the occurrence of external short circuits in adjacent modules caused by gases and particles generated in the battery module during thermal runaway, thereby delaying thermal runaway.

Claims

1. A battery module for thermal runaway delay, A battery cell stack in which multiple battery cells are stacked, A module case for housing the aforementioned battery cell stack, An end plate positioned on one side of the module case, Includes, The end plate includes a front portion and a rear portion, the rear portion being the side facing the inside of the module case, the front portion being the opposite side of the rear portion, the front portion including an upper vertical surface portion, a horizontal surface portion bent at the upper vertical surface portion and extending horizontally, and a lower vertical surface portion bent at the front end of the horizontal surface portion and extending vertically, A battery module in which flame-retardant paint is applied to the upper vertical surface and the horizontal surface of the end plate.

2. The battery module according to claim 1, wherein the end plate includes a terminal opening.

3. The battery module according to claim 2, wherein the flame-retardant paint is applied around the terminal opening on the end plate.

4. Including the terminal bus bar, The battery module according to claim 3, wherein one end of the terminal busbar is exposed through the terminal opening.

5. The battery module according to claim 4, further comprising a busbar frame disposed on one side of the battery cell stack.

6. The battery module according to claim 5, wherein the terminal busbar is arranged on the busbar frame.

7. The battery module according to claim 6, further comprising an insulating cover positioned outside the busbar frame.

8. The battery module according to claim 7, wherein the insulating cover includes an opening through which the terminal busbar is exposed.

9. The battery module according to claim 1, wherein the flame-retardant paint is applied to the upper edge of the lower vertical surface portion.

10. The battery module according to claim 9, wherein the width of the upper edge of the lower vertical surface portion to which the flame-retardant paint is applied is 5 mm or less.

11. A battery module for thermal runaway delay, A battery cell stack in which multiple battery cells are stacked, A module case for housing the aforementioned battery cell stack, An end plate positioned on one side of the module case, Includes, The end plate includes a front portion and a rear portion, the rear portion being the side facing the inside of the module case, the front portion being the opposite side of the rear portion, the front portion including an upper vertical surface portion, a horizontal surface portion bent at the upper vertical surface portion and extending horizontally, and a lower vertical surface portion bent at the front end of the horizontal surface portion and extending vertically, A battery module in which heat-resistant paint is applied to the upper vertical surface and the horizontal surface of the end plate.

12. The battery module according to claim 11, wherein the end plate includes a terminal opening.

13. The battery module according to claim 12, wherein the heat-resistant paint is applied around the terminal opening on the end plate.

14. Including the terminal bus bar, The battery module according to claim 13, wherein one end of the terminal busbar is exposed through the terminal opening.

15. The battery module according to claim 14, further comprising a busbar frame disposed on one side of the battery cell stack.

16. The battery module according to claim 15, wherein the terminal busbar is arranged on the busbar frame.

17. The battery module according to claim 16, further comprising an insulating cover positioned outside the busbar frame.

Images