Battery pack and devices containing it

Abstract

A battery pack according to one embodiment of the present invention includes at least one battery assembly containing a plurality of battery cells, and a pack frame housing at least one of the battery assemblies. The pack frame includes a bottom frame on which the battery assembly is placed and which is provided with a venting space. The battery assembly includes battery cells stacked in one direction, and a cell frame that extends along the periphery of the battery cells and covers the periphery of the battery cells. A cell vent is formed in the portion of the cell frame facing the bottom frame.

Description

Technical Field

[0001] [Cross - reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2024 - 0035065 filed on March 13, 2024 and Korean Patent Application No. 10 - 2024 - 0197354 filed on December 26, 2024, and all the contents disclosed in the documents of these Korean patent applications are incorporated herein by reference as part of this specification.

[0002] The present invention relates to a battery pack and a device including the same, and more specifically, to a battery pack and a device including the same that can prevent structural collapse by minimizing thermal runaway transfer.

Background Art

[0003] In modern society, the use of portable devices such as mobile phones, notebook computers, video cameras, and digital cameras has become common, and technological development in fields related to such mobile devices has been active. In addition, rechargeable secondary batteries are used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug - in hybrid electric vehicles (P - HEVs), etc. as a solution to problems such as air pollution caused by conventional gasoline vehicles that use fossil fuels, and the need for development related to secondary batteries is increasing.

[0004] Currently commercialized secondary batteries include nickel - cadmium batteries, nickel - hydrogen batteries, nickel - zinc batteries, lithium secondary batteries, etc. Among these, lithium secondary batteries have attracted attention because they hardly exhibit a memory effect compared to nickel - based secondary batteries, allow free charge and discharge, have a very low self - discharge rate, and have a high energy density.

[0005] Such lithium secondary batteries primarily use lithium oxides and carbon materials as the positive electrode active material and negative electrode active material, respectively. A lithium secondary battery comprises an electrode assembly in which a positive electrode plate and a negative electrode plate coated with such positive electrode active material and negative electrode active material are arranged with a separator in between, and a battery case that seals and houses the electrode assembly together with the electrolyte.

[0006] Generally, lithium secondary batteries can be classified into two types based on the shape of their casing: can-type secondary batteries, in which the electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which the electrode assembly is housed in a pouch made of aluminum laminate sheet.

[0007] For secondary batteries used in small devices, two to three battery cells are typically arranged. For secondary batteries used in medium to large devices such as automobiles, a battery module is used, which consists of numerous battery cells electrically connected. Such battery modules improve capacity and output by forming a stack of battery cells by connecting multiple battery cells in series or parallel. One or more battery modules are installed together with various control and protection systems, such as a Battery Management System (BMS), a Battery Disconnect Unit (BDU), and a cooling system, to form a battery pack.

[0008] A battery pack includes battery modules as a sub-concept, and a battery module includes battery cells as a sub-concept. The number of battery cells included in a battery module, or the number of battery modules included in a battery pack, can be determined in various ways depending on the output and capacity of the battery pack required for the electric vehicle.

[0009] In recent years, two critical challenges in battery modules and battery packs have been the control of rapid charging and thermal propagation.

[0010] First, one of the problems with rapid charging is the heat generated during the process. In other words, rapid charging requires a cooling system to manage the heat generated during the process at an appropriate level. Conventional battery modules use an edge cooling structure, which cools only one side of the battery cell (usually the bottom side). When rapid charging is applied to a battery module with an edge cooling structure, the temperature difference between the top and bottom increases, and if the cooling effect on the top is insufficient, the efficiency of rapid charging decreases. Therefore, ensuring effective cooling performance is very important for rapid charging.

[0011] Next, regarding the control of thermal propagation, if a thermal event occurs in any one of the many battery cells contained in the battery pack, it is necessary to prevent that thermal event from being propagated to the other battery cells.

[0012] If heat transfer between battery cells is not properly suppressed, it can lead to thermal events in other battery cells within the battery pack, potentially resulting in more serious consequences such as fire or explosion of the battery pack. Furthermore, fires and explosions in battery packs can cause significant damage to surrounding lives and property. Therefore, such battery packs require a configuration that can appropriately control the aforementioned thermal events and their propagation.

[0013] In summary, there is a growing demand for battery packs that have effective cooling methods for rapid charging, as well as means to suppress heat transfer between battery cells. [Overview of the Initiative] [Problems that the invention aims to solve]

[0014] The problem that this invention aims to solve is to provide a battery pack and a device including the same, which have an effective cooling means for rapid charging as well as means for suppressing heat transfer between battery cells.

[0015] However, the problems to be solved in the embodiments of the present invention are not limited to those described above, and can be extended in various ways within the scope of the technical ideas included in the present invention. [Means for solving the problem]

[0016] A battery pack according to one embodiment of the present invention includes at least one battery assembly containing a plurality of battery cells, and a pack frame housing at least one of the battery assemblies. The pack frame includes a bottom frame on which the battery assembly is placed and which is provided with a venting space. The battery assembly includes battery cells stacked in one direction, and a cell frame that continues along the periphery of the battery cells and covers the periphery of the battery cells. A cell vent is formed in the portion of the cell frame facing the bottom frame.

[0017] The cell vent section may be arranged to correspond to the venting space.

[0018] The cell frame may include a first frame covering the lower end of the battery cell, a second frame covering the upper end of the battery cell, and third and fourth frames covering both ends between the lower and upper ends of the battery cell, respectively. The cell vent portion may be formed on the first frame.

[0019] Each of the aforementioned battery cells is provided with the aforementioned cell frame, and there can be a one-to-one correspondence between the battery cell and the cell frame.

[0020] While venting gas is discharged from the battery cell, the cell vent part can communicate with the venting space of the bottom frame.

[0021] The cell vent part may protrude toward the bottom frame and be inserted into the venting space inside the bottom frame.

[0022] The battery assembly may include a cell assembly frame for housing the battery cell. The cell assembly frame may include an upper frame covering the upper part of the battery cell and a lower frame covering the lower part of the battery cell.

[0023] A vent cover part that opens at a pressure above a predetermined pressure may be disposed under the cell vent part.

[0024] The vent cover part may cover the cell vent part.

[0025] The vent cover part may protrude toward the bottom frame and be inserted into the venting space of the bottom frame.

[0026] The bottom frame may include an outer frame and an inner frame. The outer frame is disposed under the inner frame, and the venting space is provided by the outer frame and the inner frame.

[0027] There may be a plurality of the venting spaces, and the venting gas generated from the battery cell may sequentially pass through the venting spaces.

[0028] The inner frame may include a concave portion and a convex portion. The bending space may include a first bending space provided in the concave portion and a second bending space provided in the convex portion. A filtering hole connecting the first bending space and the second bending space may be formed in the inner frame.

[0029] A bending flow path that is bent multiple times may be formed inside the convex portion.

[0030] A bending device that opens or ruptures at a predetermined pressure or higher may be provided inside the convex portion.

[0031] A heat sink having at least one cooling plate disposed between at least some of the battery cells may be included.

[0032] A refrigerant may flow inside the cooling plate.

[0033] The battery cell and the cooling plate may be in surface contact.

[0034] At least one pad member disposed between at least some of the battery cells may be included.

[0035] The pack frame includes a side frame that continues along the periphery of the bottom frame, and a side bending space communicating with the bending space may be provided in the side frame. The bending gas flowing into the bending space of the bottom frame may move to the side bending space.

[0036] The device according to an embodiment of the present invention includes the battery pack.

Effects of the Invention

[0037] According to embodiments of the present invention, a cooling plate placed between the cell frame covering the periphery of the battery cell and the battery cell provides surface cooling to the battery cell, thereby improving cooling performance.

[0038] Furthermore, if a thermal event occurs in a battery cell, the high-temperature venting gas and particles ejected from that battery cell will move along a specific, intended path through the cell vent section provided in the cell frame. This minimizes the propagation of thermal events from one battery cell to other battery cells.

[0039] 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]

[0040] [Figure 1] This is a perspective view showing a battery pack according to one embodiment of the present invention. [Figure 2] Figure 1 is a perspective view showing the battery pack with the pack cover removed. [Figure 3] Figure 1 is a perspective view showing the pack frame included in the battery pack. [Figure 4] This is a perspective view showing one of the battery assemblies included in the battery pack shown in Figure 1. [Figure 5] Figure 4 is an exploded perspective view of the battery assembly. [Figure 6] Figure 5 is a perspective view showing the battery cell stack and lower frame connected together in the battery assembly. [Figure 7] Figure 6 is a perspective view showing the battery cell stack and lower frame with the pad members separated. [Figure 8] This is a perspective view showing a battery cell and cell frame according to one embodiment of the present invention. [Figure 9]Figure 8 is an exploded perspective view of the battery cell and cell frame. [Figure 10] This is a perspective view showing a battery cell relating to one embodiment of the present invention. [Figure 11] This is a cross-sectional perspective view of a battery cell coupled to a cell frame. [Figure 12] This is a cross-sectional perspective view of a battery cell coupled to a cell frame. [Figure 13] This is a perspective view showing a cell frame relating to one embodiment of the present invention. [Figure 14] This is a perspective view showing two cell frames joined together. [Figure 15] This is a perspective view showing a heat sink and pad member according to one embodiment of the present invention. [Figure 16] This is a front view showing a heat sink and pad member according to one embodiment of the present invention. [Figure 17] This is a front view showing the heat sink, pad components, and some of the cell frames. [Figure 18] This is an exploded perspective view showing the battery cell, cooling plate, and pad components coupled to the cell frame. [Figure 19] This is a perspective view showing a heat sink according to one embodiment of the present invention. [Figure 20] Figure 19 is a perspective view of a heatsink, showing one cooling plate and a cooling tube. [Figure 21] Figure 19 is a perspective view showing one of the cooling plates included in the heatsink. [Figure 22] Figure 21 is an exploded perspective view of the cooling plate. [Figure 23] Figure 19 is a front view of the heatsink. [Figure 24] This is a perspective view from below showing the battery cell stack and the lower frame joined together. [Figure 25] This is a perspective view of the battery cell stack from below. [Figure 26] This is a cross-sectional perspective view showing the result after cutting along the cutting line AA in Figure 6. [Figure 27] This is a magnified view of section "B" in Figure 26. [Figure 28] This is an exploded perspective view showing the lower frame of one embodiment of the present invention. [Figure 29] (a) is a perspective view showing a vent plate according to one embodiment of the present invention, and (b) is a cross-sectional perspective view showing a vent plate according to one embodiment of the present invention. [Figure 30] This is a perspective view showing a pack frame and battery assembly according to one embodiment of the present invention. [Figure 31] This is a cross-sectional view showing a section cut along the cutting line DD in Figure 30. [Figure 32] This is a magnified view of the "E" portion of Figure 31. [Figure 33] This is a perspective view showing the bottom frame of one embodiment of the present invention. [Figure 34] Figure 33 is a perspective view showing the vent plate positioned on the bottom frame. [Figure 35] This is a perspective view showing an inner frame and cover plate according to one embodiment of the present invention. [Figure 36] This is a magnified view of the "F" portion of Figure 35. [Figure 37] This is a perspective view of a bottom frame according to one embodiment of the present invention, with a portion of the inner frame removed. [Figure 38] This is a perspective view showing an outer frame and routing plate according to one embodiment of the present invention. [Figure 39] (a) is a partial view showing the outer frame hole, and (b) is a partial view showing the venting device connected to the outer frame hole. [Figure 40] This is a plan view of a bottom frame according to one embodiment of the present invention, with the entire inner frame removed. [Figure 41] This is a partial cross-sectional view showing a portion of the cross-section of a battery pack according to a modified embodiment of the present invention. [Modes for carrying out the invention]

[0041] Hereinafter, various embodiments of the present invention will be described 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 implemented in a variety of different forms and is not limited to the embodiments described herein.

[0042] To clearly explain the present invention, descriptive parts that are unnecessary have been omitted, and the same or similar reference numerals are used throughout the specification for identical or similar components.

[0043] Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrary for illustrative purposes, and the present invention is not necessarily limited to those shown. In the drawings, thicknesses are shown enlarged to clearly represent various layers and regions. Also, in the drawings, the thicknesses of some layers and regions are shown exaggerated for illustrative purposes.

[0044] Furthermore, when a layer, membrane, region, plate, or other part is said to be "on top of" or "above" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. Also, when a part is described as being "on top of" or "above" a reference part, it means that it is located above or below the reference part, and does not necessarily mean that it is located "above" or "above" in the opposite direction of gravity.

[0045] Furthermore, when a specification states that a certain part "includes" a certain component, unless otherwise stated, this means that it may include other components rather than excluding them.

[0046] Furthermore, throughout the specification, "on a plane" refers to the view of the subject from above, and "on a cross-section" refers to the view of a cross-section obtained by cutting the subject perpendicularly, as seen from the side.

[0047] Figure 1 is a perspective view showing a battery pack according to one embodiment of the present invention. Figure 2 is a perspective view showing the battery pack of Figure 1 with the pack cover removed. Figure 3 is a perspective view showing the pack frame included in the battery pack of Figure 1.

[0048] Referring to Figures 1 to 3, a battery pack 1000 according to one embodiment of the present invention includes at least one battery assembly 100 containing a plurality of battery cells; and a pack frame 1100 housing at least one battery assembly 100. The pack frame 1100 includes a bottom frame 1200 on which the battery assembly 100 is placed and which is provided with a venting space (VS). The battery assembly 100 includes battery cells stacked along one direction and a cell frame that continues along the periphery of the battery cells and covers the periphery of the battery cells, with a cell vent portion formed in the portion of the cell frame facing the bottom frame 1200. The cell vent portion and the venting space of the bottom frame 1200 will be described later.

[0049] In particular, the cell vent portion formed in the portion of the cell frame facing the bottom frame 1200 in the present invention encompasses both cases where the cell vent portion directly faces the bottom frame 1200 without any additional configuration between the cell vent portion and the bottom frame 1200, and cases where an additional configuration is interposed between the cell vent portion and the bottom frame 1200.

[0050] The battery assembly 100 according to this embodiment will be described below. In the present invention, the battery assembly refers to a single unit housed in the pack frame 1100, and there are no other restrictions on structural features as long as the battery cells are stacked in one direction while covered by the cell frame.

[0051] Figure 4 is a perspective view showing one of the battery assemblies included in the battery pack of Figure 1. Figure 5 is an exploded perspective view of the battery assembly of Figure 4. Figure 6 is a perspective view showing the battery cell stack and lower frame included in the battery assembly of Figure 5 joined together.

[0052] Referring to Figures 4 to 6, a battery assembly 100 according to one embodiment of the present invention includes battery cells 110 stacked along one direction; and a cell frame 300 that continues along the periphery of each battery cell 110 and covers the periphery of the battery cells 110.

[0053] Specifically, each battery cell 110 remains covered by a cell frame 300, and the battery cells 110 can be stacked in one direction to form a battery cell stack 120. That is, a cell frame 300 is provided for each battery cell 110, and there can be a one-to-one correspondence between the battery cells 110 and the cell frames 300. As an example, each battery cell 110 remains covered by a cell frame 300 and can be stacked in a direction parallel to the X-axis to form a battery cell stack 120. The detailed structure of the cell frame 300 will be described later.

[0054] The battery assembly 100 according to this embodiment may further include a cell assembly frame 200 that houses the battery cells 110. Specifically, the cell assembly frame 200 can house the battery cells 110 covered by the cell frame 300, i.e., the battery cell stack 120. The cell assembly frame 200 may include an upper frame 210 that covers the top of the battery cells 110, and a lower frame 220 that covers the bottom of the battery cells 110.

[0055] The upper frame 210 may include side portions 211 that cover both sides of the battery cell stack 120 in the direction in which the battery cells 110 are stacked, and a ceiling portion 212 that covers the top surface of the battery cell stack 120. In particular, the ceiling portion 212 can cover the top of the cell frame 300 in the battery cell stack 120. The side portions 211 may extend downward from both opposing sides of the ceiling portion 212.

[0056] On the other hand, the cell assembly frame 200 may include a mounting portion 200M, which is the part that fixes the battery assembly 100 to the pack frame described later. Mounting holes are formed in the mounting portion 200M, and bolt members pass through the mounting holes and are fastened to the pack frame described later. For example, the mounting portion 200M can be provided on the side portion 211 of the upper frame 210, and there are no particular restrictions on its number or size.

[0057] The lower frame 220 may include a first lower cover 221, a second lower cover 222, and a vent plate 223 positioned between the first and second lower covers 221 and 222. The lower frame 220 may further include an adhesive portion 224 that joins the vent plate 223 to the battery cell stack 120. The adhesive portion 224 may extend along the periphery of the vent plate 223. The lower frame 220 can be coupled with the upper frame 210 to form a cell assembly frame 200, such a cell assembly frame can cover the top, bottom, and both sides of the battery cell stack 120. The first lower cover 221, the second lower cover 222, and the vent plate 223 will be described later with reference to Figures 28, 29, etc.

[0058] Figure 7 is a perspective view showing the battery cell stack and lower frame of Figure 6 with the pad members separated. Figure 8 is a perspective view showing a battery cell and cell frame according to one embodiment of the present invention. Figure 9 is an exploded perspective view of the battery cell and cell frame of Figure 8. Figure 10 is a perspective view showing a battery cell according to one embodiment of the present invention.

[0059] Referring to Figures 7 to 10, the battery cell 110 according to this embodiment may be of various forms. For example, as shown in Figures 8 to 10, the battery cell 110 according to this embodiment may be a pouch-type battery cell. The following description will focus on pouch-type battery cells, but the battery cell 110 according to this embodiment is not limited to this, and various types of battery cells can be applied.

[0060] The battery cell 110 according to this embodiment may be in a form in which an electrode assembly having electrode leads 111 protruding in one direction or both directions is housed in a pouch case 114. Such a battery cell 110 may be in the shape of a rectangular sheet. The battery cell 110 may have a lower end 114a, an upper end 114b, and both ends 114c, 114d.

[0061] The battery cell 110 can be formed by housing the electrode assembly in a laminated sheet pouch case 114 containing a resin layer and a metal layer, and then bonding the outer periphery of the pouch case 114. As an example, the battery cell 110 may have a structure in which two electrode leads 111 face each other and protrude from one end 114c and the other end 114d of the cell body 113, respectively. In another embodiment, the battery cell 110 may have a structure in which all electrode leads 111 protrude in one direction. One of the electrode leads 111 is the positive electrode lead and the other is the negative electrode lead.

[0062] The battery cell 110 can be manufactured by bonding the ends 114c and 114d of the pouch case 114 to the lower end 114a connecting them, with the electrode assembly (not shown) housed in the pouch case 114. In other words, the battery cell 110 according to one embodiment of the present invention has a total of three sealing portions 114s, the sealing portions 114s are sealed by methods such as fusion bonding, and the remaining upper end 114b may be a folding portion. That is, the battery cell 110 according to this embodiment may be a pouch-type secondary battery in which the electrode assembly is housed inside the pouch case 114, and the outer periphery of the pouch case 114 is sealed to form the sealing portions 114s. Figure 10 only shows that sealing portions 114s are formed at both ends 114c and 114d of the pouch case 114, and the sealing portion at the lower end 114a is not shown. However, the sealing portion at the lower end 114a is folded to one side after sealing is complete for space utilization. This will be explained again in Figure 12.

[0063] The laminated sheet pouch case 114 may include an inner resin layer for sealing, a metal layer to prevent penetration of materials, and an outermost resin layer. With respect to the electrode assembly inside the pouch case 114, the inner resin layer may be positioned on the inside, the outer resin layer on the outside, and the metal layer may be positioned between the inner and outer resin layers.

[0064] The outer resin layer may have excellent tensile strength and throat resistance relative to its thickness, as well as electrical insulation, to protect the electrode assembly from the outside. Such an outer resin layer may include polyethylene terephthalate (PET) resin or nylon resin. A metal layer may prevent air, moisture, etc., from entering the pouch-type secondary battery. Such a metal layer may include aluminum (Al). The inner resin layer may be heat-sealed by applied heat and / or pressure with the electrode assembly inside. Such an inner resin layer may include casted polypropylene (CPP) or polypropylene (PP).

[0065] The pouch case 114 may be divided into two parts, and at least one of the two parts may have a recessed storage area in which an electrode assembly can be fixed. Along the outer circumference of such storage area, the inner resin layers of the two parts of the pouch case 114 may be joined together to form a sealing portion 114s. In this manner, the pouch case is sealed, and a battery cell 110, which is a pouch-type secondary battery, can be manufactured.

[0066] As described above, a battery cell 110 can consist of multiple battery cells 110 within the battery assembly 100. For example, multiple battery cells 110 can be stacked along one direction so as to be electrically interconnected to form a battery cell stack 120. For example, multiple battery cells 110 can be stacked upright along a direction parallel to the X-axis. This allows the electrode leads 111 to protrude in a direction perpendicular to the direction in which the battery cells 110 are stacked. In a battery cell 110, one electrode lead 111 can protrude in the Y-axis direction, and the other electrode lead 111 can protrude in the -Y-axis direction. If the electrode leads 111 protrude in only one direction, then the electrode leads 111 can protrude in either the Y-axis direction or the -Y-axis direction.

[0067] Figures 11 and 12 are cross-sectional perspective views of a battery cell coupled to a cell frame. Specifically, Figure 11 is a cross-sectional perspective view of a battery cell coupled to a cell frame, cut along the xy plane, and Figure 12 is a cross-sectional perspective view of a battery cell coupled to a cell frame, cut along the xz plane. Figure 13 is a perspective view showing a cell frame according to one embodiment of the present invention. Figure 14 is a perspective view showing two cell frames coupled together.

[0068] Referring together to Figures 2 and 8 to 14, the cell frame 300 according to this embodiment extends along the periphery of the battery cell 110 and can cover the periphery of the battery cell 110. A cell vent portion 300V is formed in the portion of the cell frame 300 that faces the bottom frame 1200. That is, the cell vent portion 300V is formed in the portion of the cell frame 300 that corresponds to the lower end portion 114a of the battery cell 110.

[0069] Specifically, the cell frame 300 may include a first frame 310 covering the lower end 114a of the battery cell 110; a second frame 320 covering the upper end 114b of the battery cell 110; and third and fourth frames 330 and 340 covering both ends 114c and 114d of the battery cell 110, respectively. As described above, the battery cell 110 and the cell frame 300 correspond one-to-one, and each of the battery cells 110 may be covered by each of the cell frames 300.

[0070] The cell vent section 300V can be formed on the first frame 310 of the cell frame 300. Specifically, the cell vent section 300V may be a part that guides the discharge of high-temperature venting gas and particles generated from the battery cell 110 when a thermal event or thermal runaway occurs in any one of the battery cells 110. Such a cell vent section 300V may be provided in the central part of the first frame 310 that covers the lower end portion 114a of the battery cell 110.

[0071] As an example, the cell vent section 300V may include a first section 300V1, a second section 300V2, and a third section 300V3. The first section 300V1, the second section 300V2, and the third section 300V3 extend downwards, forming an open space between them. However, this is just one exemplary structure of the cell vent section 300V, and as an open form, it is sufficient that it can guide the discharge of high-temperature venting gas and particles generated from the battery cell 110, and there are no other limitations on its form.

[0072] The portion of the first frame 310 excluding the cell vent portion 300V is in close contact with the lower end portion 114a of the battery cell 110. However, the portion corresponding to the cell vent portion 300V is open downwards, so high-temperature venting gas and particles generated from the battery cell 110 can be discharged downwards through this cell vent portion 300V. In other words, the battery assembly according to this embodiment has a directional venting structure that discharges venting gas and particles in a predetermined direction through the cell frame 300 having the cell vent portion 300V. In particular, since the cell vent portion 300V is formed in the portion of the cell frame 300 corresponding to the lower end portion 114a of the battery cell 110, a so-called "downward venting" structure is realized in which venting gas and particles are discharged downwards. The advantages of the "downward venting" structure will be explained again below.

[0073] On the other hand, referring to Figures 8 to 12, the adhesive member 130 may be attached to the portion of the lower end 114a of the battery cell 110 excluding the portion corresponding to the cell vent portion 300V. As described above, the lower end 114a of the battery cell 110 may be the sealing portion 114s (see Figures 10 and 12) where the pouch case 114 is sealed, and the upper end 114b of the battery cell 110 may be the folding portion where the pouch case 114 is folded, rather than the sealing portion. When a thermal event or thermal runaway occurs in the battery cell 110, venting gas is generated from the battery cell 110 and the internal pressure of the battery cell 110 increases. Such venting gas can be mainly discharged through the sealing portion 114s of the battery cell 110. That is, the increased internal pressure causes the seal to be released in a portion of the sealing portion 114s, and venting gas and the like are discharged through the released portion of the sealing portion 114s.

[0074] In the battery assembly 100 according to this embodiment, the battery cells 110 can be arranged such that the lower end portion 114a of each battery cell becomes a sealing portion 114s, and the upper end portion 114b of each battery cell becomes a folding portion. With this arrangement, a "lower venting" structure that discharges venting gas and particles generated from the battery cells 110 downwards is more clearly realized. Figure 12 shows the sealing portion 114s, which corresponds to the lower end portion 114a of the battery cell 110, folded after sealing is complete for space utilization.

[0075] On the other hand, it is preferable that the venting gas of the battery cell 110 be discharged downwards, particularly through the cell vent portion 300V of the cell frame 300. For this purpose, the adhesive member 130 can be attached to the portion of the lower end 114a of the battery cell 110 that does not correspond to the cell vent portion 300V. The adhesive member 130 may be an adhesive tape, for example.

[0076] In the lower end portion 114a of the battery cell 110, the portion to which the adhesive member 130 is attached is sealed to a degree that is enhanced by the adhesive member 130, so the seal is not released even if the internal pressure of the battery cell 110 increases. On the other hand, in the lower end portion 114a of the battery cell 110, the portion to which the adhesive member 130 is not attached has a relatively lower degree of sealing, so the seal is released earlier than in the portion to which the adhesive member 130 is attached. As a result, the discharge of venting gas is guided to the portion of the lower end portion 114a of the battery cell 110 that corresponds to the cell vent portion 300V (i.e., the portion without adhesive member), and the venting gas can be discharged downwards through the cell vent portion 300V.

[0077] Referring again to Figures 6, 7, 8, 13, and 14, in the battery cell stack 120 according to this embodiment, adjacent cell frames 300 are joined together, and the battery cells 110 located inside them are fixed. There are no particular restrictions on the method of joining the cell frames 300, but joining may be done by physical restraint force. For example, each cell frame 300 may include a hook projection 300P and a hook groove 300G. The hook projection 300P may protrude toward another adjacent cell frame 300. The cell frames 300 may be joined in a manner in which the hook projection 300P of any one cell frame 300 is hook-coupled to the hook groove 300G of another adjacent cell frame 300. Figure 14 shows how such hook joining is performed between two cell frames 300. This joining between the hook projection 300P and the hook groove 300G is performed successively for each adjacent cell frame 300, so that a large number of cell frames 300 can all be joined.

[0078] Each battery cell 110 is covered by a cell frame 300, and these cell frames 300 can be joined together to form a battery cell stack 120. A battery cell stack 120 that includes cell frames 300 is structurally more stable and can withstand external vibrations and shocks better than a stack of only battery cells 110 without cell frames 300. If only battery cells 110 are stacked without cell frames 300, the battery cell stack may not be able to maintain its shape against external vibrations and shocks, potentially leading to collapse. Furthermore, in the case of a battery cell stack 120 that includes cell frames 300, since it is assembled in units of cell frames 300, replacement of cell frames 300 can be easily performed. In other words, even after the battery cell stack 120 has already been manufactured, there is the advantage that a problematic battery cell 110 can be easily replaced by disassembling and reassembling the cell frame 300.

[0079] The heat sink and pad members included in the battery assembly according to this embodiment will be described in detail below.

[0080] Figures 15 and 16 are a perspective view and a front view, respectively, showing a heat sink and pad member according to one embodiment of the present invention. Figure 17 is a front view showing the heat sink, pad member, and some cell frames. Specifically, Figure 17 illustrates how four cell frames 300 are interposed between the cooling plate 410 of the heat sink 400 and the pad member 500. Figure 18 is an exploded perspective view showing the battery cells coupled to the cell frames, along with the cooling plate and pad member.

[0081] Referring to Figures 15 to 18, the battery assembly 100 according to this embodiment may include a heat sink 400 having at least one cooling plate 410 positioned between at least one of the battery cells 110. A coolant can flow inside the cooling plate 410. Specifically, the cooling plate 410 has a coolant path, which is a space through which the coolant flows, and can come into contact with the battery cells 110.

[0082] Specifically, the battery cell 110 and the cooling plate 410 can be in surface contact. At least one surface of the battery cell 110 can be in contact with the cooling plate 410. More specifically, one surface of the cooling plate 410 can be in contact with one surface of the cell body 113 (see Figure 10) of the battery cell 110. One surface of the battery cell 110 can be in contact with the cooling plate 410, or both surfaces of the battery cell 110 can be in contact with the cooling plate 410. That is, at least one surface of the battery cell 110 can be in direct surface contact with the cooling plate 410.

[0083] The cooling plate 410 is plate-shaped and can provide surface cooling for the battery cell 110. The refrigerant flowing inside the cooling plate 410 may be cooling water. The battery assembly 100 according to this embodiment may have a water-cooled cooling structure.

[0084] Conventional battery assemblies have an edge cooling structure in which a thermal resin layer is in contact with the edges of the battery cells, and heat from the battery cells is dissipated by the direct or indirect contact of this thermal resin layer with a heat sink. On the other hand, the battery assembly 100 according to this embodiment may have a surface cooling structure in which a cooling plate 410 through which a coolant flows is interposed between the battery cells 110 and contacts one surface of the cell body 113 (see Figure 10) of the battery cell 110. Since one surface of the cell body 113 (see Figure 10) of the battery cell 110 can come into contact with one surface of the cooling plate 410, the cooling area is much larger, which has the advantage of superior cooling performance compared to conventional battery assemblies.

[0085] In recent years, rapid charging has become an essential requirement for battery assemblies. However, one of the problems with rapid charging is the heat generated during the process. For rapid charging to work, a cooling system is essential to manage the heat generated during the process at an appropriate level. When rapid charging is applied to conventional battery assemblies with edge cooling structures, the temperature difference between the upper and lower parts increases, and in the case of the upper part where the cooling effect is insufficient, the rapid charging efficiency inevitably decreases. On the other hand, in the case of the battery assembly 100 according to this embodiment, the cooling plate 410 makes surface contact with the battery cell 110 and directly cools the battery cell 110, thus providing excellent cooling performance that can control the heat generated during rapid charging.

[0086] There are no particular restrictions on the number or size of the cooling plates 410, as long as surface cooling can be performed for the battery cells 110 within the battery assembly 100. The number of cooling plates 410 can be appropriately changed considering the size, capacity, and heat generation of the battery assembly 100. Furthermore, there are no particular restrictions on the area of ​​the cooling plates 410, as long as they can cover 60% or more of the surface area of ​​one side of the battery cell 110. However, although multiple cooling plates 410 are provided within the battery assembly 100, it is preferable to ensure that there are enough cooling plates 410 so that one side of all battery cells 110 can come into contact with the cooling plates 410.

[0087] On the other hand, referring to Figure 10, the sealing portions 114s at both ends 114c and 114d of the battery cell 110, where the electrode leads 111 protrude, correspond to the so-called terrace portion of the battery cell 110. Such a terrace portion is thinner than the cell body 113 of the battery cell 110. Referring again to Figure 18, the thinness of the terrace portion may create a slight gap between the terrace portion of the battery cell 110 and the cooling plate 410. To fill the gap between the terrace portion of the battery cell 110 and the cooling plate 410, an additional spacer 700 may be provided between the terrace portion of the battery cell 110 and the cooling plate 410.

[0088] On the other hand, referring again to Figures 15 to 18, the battery assembly according to this embodiment may include at least one pad member 500 positioned between at least one of the battery cells 110. The pad member 500 may be a foam member having thermal insulation properties. There are no particular restrictions on the material of the pad member 500, as long as it has thermal insulation properties and a predetermined elasticity. For example, the pad member 500 may include a silicone material or an aerogel material.

[0089] In one embodiment of the present invention, cooling plates 410 or pad members 500 may be placed between battery cells 110. Specifically, in a battery cell stack 120, the battery cells 110 are stacked while covered by cell frames 300, but either cooling plates 410 or pad members 500 may be placed between adjacent battery cells 110. More specifically, as shown in Figures 15 to 17, cooling plates 410 and pad members 500 are arranged alternately one at a time along the X-axis direction, which is the direction in which the battery cells 110 are stacked. The battery cells 110 coupled to the cell frames 300 may be interposed in the space (S, see Figure 16) between such cooling plates 410 and pad members 500. Figure 17 shows that each of the four cell frames 300 is interposed between a cooling plate 410 and a pad member 500. Although not shown in Figure 17 because the battery cell 110 is obscured by the cell frame 300, the battery cell 110 is located inside the cell frame 300.

[0090] As a result, as shown in Figure 18, in any one of the battery cells 110, one side of the battery cell 110 can be in contact with the cooling plate 410 of the heat sink 400, and the opposite side of the battery cell 110 can be in contact with the pad member 500. However, this is just one example, and in other embodiments of the present invention, cooling plates 410 can be provided on both sides of the battery cell 110 without the pad member 500. The thermal propagation prevention function and expansion control function of the cooling plate 410 and the pad member 500 will be described later.

[0091] The structure of the heat sink according to this embodiment will be described in detail below.

[0092] Figure 19 is a perspective view showing a heat sink according to one embodiment of the present invention. Figure 20 is a perspective view showing one cooling plate and cooling tube in the heat sink of Figure 19. Figure 21 is a perspective view showing one of the cooling plates included in the heat sink of Figure 19. Figure 22 is an exploded perspective view of the cooling plate of Figure 21. Figure 23 is a front view of the heat sink of Figure 19.

[0093] Referring to Figures 19 to 23, the heat sink 400 according to this embodiment may include a cooling plate 410 for surface cooling of the battery cell 110, and a cooling tube 420 connected to the cooling plate 410.

[0094] First, the cooling plate 410 may include a first cooling cover 411, a second cooling cover 412, and a central cooling plate 413 positioned between the first cooling cover 411 and the second cooling cover 412. The first cooling cover 411, the central cooling plate 413, and the second cooling cover 412 may be arranged sequentially along the -X axis in the direction in which the battery cells 110 are stacked.

[0095] A refrigerant path (CP) may be provided in the central cooling plate 413, which is a path through which the refrigerant flows. The path for the refrigerant can be completed by sealing such a refrigerant path (CP) between the first cooling cover 411 and the second cooling cover 412. Figure 22 shows the refrigerant path (CP) as a winding path as one example, but there are no special restrictions on the width, shape, area, etc. of the refrigerant path (CP) as long as the refrigerant can flow through it. In another embodiment, the refrigerant path (CP) can be realized as a single open space. The width, shape, area, etc. of the refrigerant path (CP) can be appropriately adjusted considering the refrigerant flow velocity and flow rate.

[0096] The cooling plate 410 may include an inlet 410N and an outlet 410U connected to a refrigerant path (CP). Each of the inlet 410N and outlet 410U of the cooling plate 410 is connected to a cooling tube 420. Specifically, the cooling tube 420 may include a first cooling tube 421 and a second cooling tube 422, where the first cooling tube 421 is connected to the inlet 410N of the cooling plate 410 and the second cooling tube 422 is connected to the outlet 410U of the cooling plate 410.

[0097] The first cooling tube 421 and the second cooling tube 422 may be connected to a refrigerant circulation system (not shown) located inside or outside the battery pack. Refrigerant moving from the refrigerant circulation system along the first cooling tube 421 can flow into the refrigerant path (CP) via the inlet 410N of the cooling plate 410 and flow through the inside of the cooling plate 410. Subsequently, the refrigerant discharged from the refrigerant path (CP) via the outlet 410U of the cooling plate 410 can flow along the second cooling tube 422 and then be recovered into the refrigerant circulation system again. Through this process, a pure refrigerant loop structure can be realized within the battery assembly 100. Heat generated from the battery cells 110 inside the battery assembly 100 is transferred to the refrigerant flowing into the refrigerant path (CP) of the cooling plate 410 and discharged to the outside of the battery assembly 100 by the second cooling tube 422. Subsequently, the refrigerant cooled again in the refrigerant circulation system can flow back into the refrigerant path (CP) of the cooling plate 410 via the first cooling tube 421. In other words, the battery assembly 100 according to this embodiment can have a structure that dissipates heat generated from the battery cells 110 by a coolant flowing along the heat sink 400.

[0098] On the other hand, as shown in Figure 23, a chamfered portion 410CH may be provided at one end of the cooling plate 410. The chamfered portion 410CH may be a portion in which the thickness gradually decreases from one end of the cooling plate 410 toward the outside of the cooling plate 410.

[0099] In a battery cell stack 120 formed by stacking battery cells 110 mounted on a cell frame 300 in one direction, a cooling plate 410 can be inserted into the gaps between the battery cells 110. Since a chamfer portion 410CH is provided at one end of the cooling plate 410, the cooling plate 410 can be easily inserted between the battery cells 110 when it is assembled into the battery cell stack 120. The cooling plate 410 can be pressed in while making close contact with the battery cells 110, including the chamfer portion 410CH.

[0100] Referring again to Figures 5 to 9, the battery assembly 100 may further include busbars 610 and terminal busbars 620 that connect to the electrode leads 111 of the battery cells 110. The busbars 610 and terminal busbars 620 are electrically connected to the electrode leads 111 of the battery cells 110. As an example, the busbars 610 and terminal busbars 620 can be joined to the electrode leads 111 by welding. The busbars 610 and terminal busbars 620 are located on both sides (the Y-axis plane and the -Y-axis plane) of the battery cell stack 120 that are not covered by the cell assembly frame 200.

[0101] The battery cells 110 are electrically connected in series or parallel via such busbars 610.

[0102] The terminal busbar 620 is electrically connected to the electrode leads 111 of some of the battery cells 110, and a portion of it can be exposed to the outside of the battery assembly 100. The battery assembly 100 can form HV (High Voltage) connections with other battery assemblies and electrical components via such terminal busbar 620. Here, an HV connection is a connection that acts as a power source to supply power requiring high voltage, and refers to connections between battery cells or between battery assemblies.

[0103] On the other hand, although not specifically shown in the diagram, the battery assembly 100 may include a connector. The connector (not shown) is a component for LV (Low Voltage) connections of the battery assembly 100. LV connections refer to electrical connections that require relatively low voltage, such as battery electrical components. For example, a sensing component (not shown) can sense voltage data from the battery cells 110 and internal temperature data from the battery assembly 100, and a connector connected to the sensing component can send the sensed voltage data and temperature data to a BMS (Battery Management System) located outside the battery assembly 100. Therefore, a part of the connector may also be exposed to the outside of the battery assembly 100.

[0104] The functions of the cell frame 300, the cooling plate 410 of the heat sink 400, and the pad member 500 in the battery assembly 100 according to this embodiment will be described in more detail below.

[0105] Referring to Figures 8 to 22, the cell frame 300 according to this embodiment extends along the periphery of each battery cell 110 and covers the periphery of the battery cell 110, so that one surface of the cell body 113 of the battery cell 110 is exposed without being obstructed by the cell frame 300. The cell frame 300 can stably fix the battery cell 110 and at the same time guide one surface of the cell body 113 of the battery cell 110 to contact the cooling plate 410 of the heat sink 400. In other words, the cell frame 300 and the cooling plate 410 enable surface cooling of the battery cell 110 in the battery cell stack 120. As a result, the battery assembly 100 according to this embodiment can have excellent cooling performance that can control heat generation during rapid charging.

[0106] Since one surface of the cell body 113 of the battery cell 110 is in close contact with the cooling plate 410 or pad member 500, even if a thermal event or thermal runaway occurs in the battery cell 110, heat propagation and venting gas discharge are difficult in the surface direction, i.e., in the X-axis direction or -X-axis direction, which is the direction in which the battery cells 110 are stacked. As a result, high-temperature venting gas and particles caused by thermal runaway in the battery cell 110 are likely to be released through the periphery of the battery cell 110, namely the lower end 114a, upper end 114b, and both ends 114c, 114d. High-temperature venting gas and particles are likely to be discharged as the seal is released at the lower end 114a and both ends 114c, 114d, where the seal portion 114s is provided. In particular, the sealed portion 114s at both ends 114c and 114d of the battery cell 110 where the electrode leads 111 protrude is called the terrace part. In conventional battery assemblies, venting gas was mainly released at such terrace parts as the seal was released.

[0107] However, according to this embodiment, the first to fourth frames 310, 320, 330, and 340 of the cell frame 300 are in close contact with the lower end 114a, upper end 114b, and both ends 114c, 114d of the battery cell, respectively, thus limiting the discharge of venting gas and particles through the periphery of the battery cell 110. Instead, a cell vent section 300V that opens downwards is provided in the portion of the cell frame 300 corresponding to the lower end 114a of the battery cell, i.e., the first frame 310. Therefore, high-temperature venting gas and particles generated during the thermal runaway process of the battery cell 110 can be guided to be discharged only into this cell vent section 300V. In other words, the battery assembly 100 according to this embodiment induces directional venting downwards, i.e., "downward venting," by the cell frame 300 equipped with the cell vent section 300V. Furthermore, as explained earlier, the adhesive member 130 attached to the portion of the lower end 114a of the battery cell 110 that is not corresponding to the cell vent portion 300V more clearly ensures that only the cell vent portion 300V is vented.

[0108] On the other hand, as will be described later, with the battery assembly 100 housed in the pack frame, the venting gas and particles discharged from the cell vent section 300V can be discharged to the outside of the pack frame via the inside of the bottom frame of the pack frame. This will be described in detail later with reference to Figures 30 to 40.

[0109] The battery assembly 100 contains high-voltage current paths, such as the HV (High Voltage) connections of the busbars 610 and terminal busbars 620. Here, HV connections are connections that act as power sources to supply power requiring high voltage, and refer to connections between battery cells and connections between battery assemblies. In this case, if high-temperature gases or particles from thermal events of the battery cell 110 come into contact with high-voltage paths such as HV connections, short circuits or arc discharges may occur, which could lead to additional explosions and flames. In particular, the terrace portion is adjacent to the electrode leads 111, busbars 610, etc., and the venting gas discharged through the terrace portion directly affects the HV connections, making it more dangerous. On the other hand, in the case of the battery pack according to this embodiment, as mentioned above, it has a "lower venting" structure via the cell vent portion 300V, so that high-temperature gases and particles from thermal events can be discharged downwards. In particular, as will be described later, they can be discharged to the outside via the bottom frame of the pack frame. Therefore, there is no risk of high-temperature gases or particles coming into contact with high-voltage paths such as HV connections, ultimately improving safety against thermal runaway phenomena.

[0110] On the other hand, as explained earlier, one surface of the cell body 113 of the battery cell 110 is in close contact with the cooling plate 410 and the pad member 500. Therefore, the cooling plate 410 and the pad member 500 can minimize the transfer of heat from the thermal runaway phenomenon occurring in the battery cell 110 to other adjacent battery cells 110. In other words, the cooling plate 410 achieves excellent cooling performance that can control the heat generation during rapid charging through its surface cooling structure, while simultaneously preventing thermal propagation between battery cells 110. In particular, the cooling plate 410 has a configuration in which a coolant flows inside, which can lower the thermal runaway temperature of the battery cell 110 and also blocks heat in the lateral direction, making it effective in preventing thermal propagation between battery cells 110. Similarly, the pad member 500 can also prevent thermal propagation between battery cells 110. If the pad member 500 contains a material with excellent heat insulation properties, it is even more effective in preventing thermal propagation.

[0111] On the other hand, during repeated charging and discharging, the battery cell 110 may undergo a phenomenon called swelling, where its internal electrolyte decomposes, generating gas and causing the battery cell 110 to swell. In the case of swelling of the battery cell 110, the battery cell 110 expands in the thickness direction. That is, the battery cell 110 may expand along the direction in which the battery cells 110 are stacked (parallel to the X-axis). The pad member 5000 according to this embodiment can absorb and control the swelling of the battery cell 110. This prevents the battery assembly 100 from deforming beyond its deformation limit due to the swelling of the battery cell 110. The cooling plate 410, which is in contact with the other side of the battery cell 110, can also absorb some of the swelling of the battery cell 110.

[0112] The following describes in detail the vent plate and vent cover portion according to one embodiment of the present invention.

[0113] Figure 24 is a perspective view from below showing the battery cell stack and the lower frame joined together. Figure 25 is a perspective view from below showing the battery cell stack. Figure 26 is a cross-sectional perspective view showing the stack cut along the cutting line AA in Figure 6. Figure 27 is a partial drawing showing an enlarged view of portion "B" in Figure 26. Figure 28 is an exploded perspective view showing the lower frame according to one embodiment of the present invention. Figures 29(a) and (b) are a perspective view and a cross-sectional perspective view showing the vent plate according to one embodiment of the present invention, respectively. In particular, Figure 29(b) shows the stack cut along the cutting line CC in Figure 29(a).

[0114] Referring to Figures 5, 6 and 24-29, as described above, the battery assembly 100 according to this embodiment may include a cell assembly frame 200 that houses the battery cells 110, and the cell assembly frame 200 may include an upper frame 210 that covers the top of the battery cells 110; and a lower frame 220 that covers the bottom of the battery cells 110.

[0115] A vent cover section 220VC, which opens above a predetermined pressure, may be located below the cell vent section 300V. For example, the vent cover section 220VC, which opens above a predetermined pressure, may be formed on the lower frame 220. For example, the lower frame 220 may include a first lower cover 221, a second lower cover 222, and a vent plate 223 located between the first lower cover 221 and the second lower cover 222.

[0116] A first lower cover 221, a vent plate 223, and a second lower cover 222 may be arranged sequentially along the direction from one end 114d to the other end 114c of the battery cell 110. That is, the vent plate 223 is positioned at a location corresponding to the cell vent portion 300V of the cell frame 300, and a vent cover portion 220VC may be provided on such a vent plate 223.

[0117] The vent cover portion 220VC can cover the cell vent portion 300V of the cell frame 300. Specifically, the vent cover portion 220VC can cover the lower part of the cell vent portion 300V of the cell frame 300. The vent plate 223, including the vent cover portion 220VC, may contain fire-resistant material. For example, the vent plate 223 may contain MICA material.

[0118] The vent cover section 220VC may be a structure that opens when a predetermined pressure is applied by the venting gas discharged through the cell vent section 300V. As long as this function is performed, there are no particular restrictions on the structure of the vent cover section 220VC, nor are there any particular restrictions on the pressure criteria for opening. The pressure criteria for opening may vary depending on the number, size, and composition of the battery cells included in the battery assembly.

[0119] As an example, the vent cover portion 220VC according to this embodiment may include a connecting portion 220C which is connected to the vent plate 223, and open slits 220S may be formed on the remaining three sides excluding the connecting portion 220C. That is, the vent cover portion 220VC can be provided on the vent plate 223 by forming slits 220S on the remaining three sides excluding the connecting portion 220C. There is no particular limit to the number of vent cover portions 220VC provided on the vent plate 223, but as an example, the number of vent cover portions 220VC is the same as the number of cell vent portions 300V in the battery cell stack 120, and each vent cover portion 220VC can correspond one-to-one with each cell vent portion 300V.

[0120] Normally, the vent cover section 220VC covers the lower part of the cell vent section 300V. However, when venting gas is discharged from the battery cell 110 and a pressure exceeding a predetermined level is applied to the vent cover section 220VC, the vent cover section 220VC bends in the opposite direction to the direction in which the cell vent section 300V is located, and the vent cover section 220VC is opened. As a result, the venting gas generated from the battery cell can be discharged through the cell vent section 300V and the vent cover section 220VC.

[0121] On the other hand, the lower frame 220 may include an adhesive portion 224 that joins the vent plate 223 to the battery cell stack 120. Such an adhesive portion 224 may extend along the periphery of the vent plate 223. More specifically, the adhesive portion 224 may be provided on the periphery of the vent plate 223, and the vent plate 223 may be attached to the lower end of the cell frame 300, i.e., the first frame 310 of the cell frame 300, via the adhesive portion 224. Because the adhesive portion 224 is attached to the periphery of the vent plate 223, venting gas and particles discharged from the cell vent portion 300V are prevented from leaking to other parts other than the vent cover portion 220VC.

[0122] Furthermore, referring to Figures 13, 15, 18, 19, and 27, the cooling plate 410 according to this embodiment may include a cooling plate projection 410P that protrudes in a manner corresponding to the cell vent portion 300V of the cell frame 300. The cooling plate projection 410P can protrude downwards at the lower edge of the cooling plate 410 so as to face the cell vent portion 300V.

[0123] Furthermore, the pad member 500 may include a pad member projection 500P that protrudes in a manner corresponding to the cell vent portion 300V of the cell frame 300. The pad member projection 500P can protrude downwards from the lower edge of the pad member 500 so as to face the cell vent portion 300V.

[0124] As shown in Figure 13, the cell vent section 300V may include a first section 300V1, a second section 300V2, and a third section 300V3, but the section facing the third section 300V3 can be opened without other components.

[0125] In this configuration, a cooling plate 410 or pad member 500 is placed between the battery cells 110, and a cooling plate protrusion 410P or pad member protrusion 500P may be placed in the portion of the cell vent section 300V facing the third portion 300V3.

[0126] Specifically, as shown in Figure 27, a pad member protrusion 500P may be positioned opposite the third portion 300V3 of any one cell vent section 300V, and a cooling plate protrusion 410P may be positioned opposite the third portion 300V3 of another cell vent section 300V adjacent to it.

[0127] The first portion 300V1 and the second portion 300V2 of the cell vent section 300V come into contact with either the cooling plate protrusion 410P or the pad member protrusion 500P, forming a venting path in the cell vent section 300V. That is, the space enclosed by the first portion 300V1, the second portion 300V2, the third portion 300V3, and the cooling plate protrusion 410P or the pad member protrusion 500P can become a venting path (VP, see Figure 27) through which the venting gas passes. The lower part of the venting path (VP) is blocked by the vent cover portion 220VC of the vent plate 223. Normally, the venting path (VP) is blocked by the vent cover portion 220VC, but if a pressure exceeding a predetermined level is applied to the vent cover portion 220VC, the vent cover portion 220VC bends downward, opening the venting path (VP). The venting gas generated from the battery cell 110 can be discharged downwards through the venting path (VP) of the cell vent section 300V.

[0128] On the other hand, referring again to Figure 5, the upper frame 210 of the cell assembly frame 200 may include side portions 211 and a top portion 212 that cover the battery cell stack 120. Such an upper frame 210 can protect the battery cell stack 120 and control the expansion of the battery cells 110. Although a cell vent portion 300V is provided in the cell frame 300, there may be venting gas leaking between the cell frame 300 to other parts, but the upper frame 210 can block the leaking venting gas from diffusing to the outside of the battery assembly 100.

[0129] Referring again to Figures 1 to 3, a venting space is provided in the bottom frame 1200 on which the battery assembly 100 is placed. The venting space will be explained in detail with other drawings. Figures 1 and 2 illustrate the battery pack 1000 with six battery assemblies 100 placed on the bottom frame 1200.

[0130] The pack frame 1100 may include side frames 1300 that extend along the periphery of the bottom frame 1200. For example, the side frames 1300 may include a first side frame 1310, a second side frame 1320, a third side frame 1330, and a fourth side frame 1340. The first side frame 1310, the second side frame 1320, the third side frame 1330, and the fourth side frame 1340 are arranged along the four sides of the periphery of the rectangular bottom frame 1200. The bottom frame 1200 and the side frames 1300 provide an open storage space in which the battery assembly 100 is placed. After the battery assembly 100 is placed in the storage space, the open top of the storage space can be covered with a pack cover 1400. The pack cover 1400 is joined to the side frames 1300 of the pack frame 1100, for example by welding or by using adhesive. The battery assembly 100 can be sealed by the pack frame 1100 and the pack cover 1400. A gasket may also be interposed between the pack cover 1400 and the side frame 1300 to enhance the seal.

[0131] On the other hand, the battery pack 1000 according to this embodiment may include a mounting beam 1300M provided on the side frame 1300 for fixing the battery pack 1000. As an example, the mounting beam 1300M is shown formed on the side frame 1300 in Figures 1 to 3. The mounting beam 1300M can be utilized when attaching the battery pack 1000 to a device. For example, when attaching the battery pack 1000 to a vehicle device, the mounting beam 1300M may be fixed to the vehicle's chassis.

[0132] Furthermore, the battery pack 1000 according to this embodiment may include vertical beams 1800 that are placed on the bottom frame 1200 and demarcate the space in which the battery assemblies 100 are located. As an example, Figures 2 and 3 show three vertical beams 1800 that divide the storage space in which six battery assemblies 100 are placed into three areas.

[0133] Figure 30 is a perspective view showing a pack frame and battery assembly according to one embodiment of the present invention. Figure 31 is a cross-sectional view showing a cross-section cut along the cutting line DD of Figure 30. Figure 32 is a partial drawing showing an enlarged view of portion "E" of Figure 31. Figure 33 is a perspective view showing a bottom frame according to one embodiment of the present invention. Figure 34 is a perspective view showing the vent plate positioned on the bottom frame of Figure 33. That is, other parts of the battery assembly are omitted from the illustration, and only the vent plate 223 of the battery assembly positioned on the bottom frame 1200 is shown in Figure 34.

[0134] Referring to Figures 24, 25, and 30-34, the bottom frame 1200 is provided with a venting space (VS) to which venting gas and particles discharged from the cell vent section 300V move. The cell vent section 300V of the cell frame 300 can be positioned to correspond to the venting space (VS) of the bottom frame 1200. Specifically, the cell vent section 300V of the cell frame 300 can communicate with the venting space (VS) of the bottom frame 1200. More specifically, while venting gas is discharged from the battery cell 110 due to thermal runaway in the battery cell 110, the cell vent section 300V can communicate with the venting space (VS) of the bottom frame 1200. This allows the venting gas to move from the cell vent section 300V to the venting space (VS) of the bottom frame 1200.

[0135] The cell vent section 300V, which covers the lower part of the cell vent section 300V of the cell frame 300, may normally prevent communication between the cell vent section 300V and the venting space (VS) of the bottom frame 1200. However, once the vent cover section 220VC is opened by the venting gas discharged through the cell vent section 300V, communication between the cell vent section 300V and the venting space (VS) of the bottom frame 1200 is established, allowing the venting gas to move from the cell vent section 300V to the venting space (VS) of the bottom frame 1200.

[0136] The cell vent section 300V may protrude toward the bottom frame 1200 and be inserted toward the venting space (VS) inside the bottom frame 1200. Similarly, the portion where the vent cover section 220VC is formed may protrude toward the bottom frame 1200 and be inserted toward the venting space (VS) inside the bottom frame 1200. This prevents venting gas (VG) from leaking to other areas when the vent cover section 220VC is opened, and guides all venting gas (VG) to move into the venting space (VS) of the bottom frame 1200.

[0137] High-temperature venting gas and particles that flow into the venting space (VS) can be discharged to the outside of the battery pack 1000. The venting gas and particles flow along the venting space (VS) provided inside the bottom frame 1200 and can ultimately be discharged to the outside of the battery pack 1000. The battery pack 1000 according to this embodiment has a so-called "bottom venting" structure that uses the bottom frame 1200 to discharge high-temperature venting gas and particles to the outside. If high-temperature venting gas and particles from thermal events of the battery cell 110 come into contact with a high-voltage path such as an HV connection, there is a possibility of short circuits or arc discharges occurring, which could lead to additional explosions and flames. On the other hand, in the case of the battery pack 1000 according to this embodiment, as mentioned above, it has a "bottom venting" structure, so high-temperature venting gas and particles from thermal events are discharged downwards, i.e., into the bottom frame 1200. Therefore, there is no risk of high-temperature venting gases or particles coming into contact with high-voltage paths such as HV connections, ultimately improving safety against thermal runaway phenomena.

[0138] Below, as an example, the detailed structure of the bottom frame 1200 will be described in detail.

[0139] Figure 35 is a perspective view showing an inner frame and cover plate according to one embodiment of the present invention. Figure 36 is a partial drawing showing an enlarged view of portion "F" in Figure 35.

[0140] Referring together to Figures 30 to 36, a bottom frame 1200 according to one embodiment of the present invention may include an outer frame 1210 and an inner frame 1220. As one example of the present invention, a venting space (VS) can be provided by the outer frame 1210 and the inner frame 1220 of the bottom frame 1200. The outer frame 1210 may be a plate located at the bottom of the battery pack 1000, and such an outer frame 1210 may be coupled to a side frame 1300. The outer frame 1210 may be located below the inner frame 1220. The battery assembly 100 may be placed on the inner frame 1220.

[0141] The venting spaces (VS) according to this embodiment may be provided in multiple quantities. The venting gas generated from the battery cell 110 can sequentially pass through multiple venting spaces (VS). As the venting gas flows sequentially through the multiple partitioned venting spaces (VS), the temperature of the venting gas and the particles contained therein is lowered, and the particles contained in the venting gas can be filtered. Ultimately, it is possible to prevent the venting gas and particles from causing an explosion inside the battery pack 1000.

[0142] The venting space (VS) according to one embodiment of the present invention may include a first venting space (VS1) and a second venting space (VS2). The first venting space (VS1) and the second venting space (VS2) can be separated by a portion of the inner frame 1220 in which the filtration holes 1220H are formed.

[0143] There are no particular restrictions on the position or arrangement of the first venting space (VS1) and the second venting space (VS2) within the bottom frame 1200. For example, the first venting space (VS1) and the second venting space (VS2) may be arranged along a direction parallel to one surface of the bottom frame 1200. The first venting space (VS1) and the second venting space (VS2) may be arranged along a direction parallel to one surface of the outer frame 1210 of the bottom frame 1200. Figures 30 to 36 show, as an example, how the first venting space (VS1) and the second venting space (VS2) are arranged along a direction parallel to the Y-axis. Although not specifically shown, as another example, the first venting space and the second venting space may be arranged along a direction perpendicular to one surface of the bottom frame 1200. In other words, the first venting space and the second venting space are arranged to have a layered structure along the height direction perpendicular to one surface of the bottom frame 1200, and the venting gas can move sequentially through the first venting space and the second venting space with such a layered structure.

[0144] The inner frame 1220 is a plate-shaped member, but may include recesses 1221 and protrusions 1222. The recesses 1221 and protrusions 1222 may be alternately arranged along the Y-axis direction of the inner frame 1220. On the other hand, cover plates 1500 or the like may be joined to both sides of the inner frame 1220 to form a venting space (VS). The inner frame 1220 and the cover plates 1500 may be joined by methods such as welding.

[0145] As one example of the present invention, the venting space (VS) may include a first venting space (VS1) provided in a recess 1221 and a second venting space (VS2) provided in a protrusion 1222. The first venting space (VS1) and the second venting space (VS2) can be realized by the recess 1221 and protrusion 1222 of the inner frame 1220. For example, the portion of the inner frame 1220 where the recess 1221 is surrounded by the cover plate 1500 and the vent plate 223 of the battery assembly 100 may correspond to the first venting space (VS1). That is, the vent cover portion 220VC is opened, and the venting gas discharged from the cell vent portion 300V can move into the first venting space (VS1).

[0146] Furthermore, the portion of the inner frame 1220 where the protrusion 1222 is surrounded by the cover plate 1500 may correspond to a second venting space. The inner frame 1220 may also include a filtration hole 1220H that connects the first venting space (VS1) and the second venting space (VS2). There may be multiple filtration holes 1220H. As shown in Figures 32 and 36, the venting gas (VG) flowing into the first venting space (VS1) may move to the second venting space (VS2) via the filtration holes 1220H. Particles, ash, by-products, etc., contained in the high-temperature venting gas (VG) can be filtered out first by passing through such filtration holes 1220H. In other words, in the case of the bottom frame 1200 according to this embodiment, the venting space (VS) is divided into a first venting space (VS1) and a second venting space (VS2), and by connecting the first venting space (VS1) and the second venting space (VS2) via a filtration hole 1220H, the function of primary filtration of high-temperature venting gas (VG) can be achieved.

[0147] As described above, the cell vent section 300V and the vent cover section 220VC may each protrude toward the bottom frame 1200 and be inserted toward the venting space (VS) inside the bottom frame 1200. In particular, the cell vent section 300V and the vent cover section 220VC may be inserted toward the first venting space (VS1).

[0148] On the other hand, a gas shield 1600 is positioned in the recess 1221 of the inner frame 1220. Specifically, in adjacent battery assemblies 100 along the X-axis, a gas shield 1600 may be positioned in the recess 1221 to separate the first venting space (VS1) located under one battery assembly 100 from the first venting space (VS1) located under another battery assembly 100. Such a gas shield 1600 can prevent venting gas discharged from one battery assembly 100 into the first venting space (VS1) from flowing back into the first venting space (VS1) located under the other adjacent battery assembly 100. In other words, the gas shield 1600 according to this embodiment can correspond to a member that independently separates the first venting space (VS1) so that each battery assembly 100 has its own independent first venting space (VS1). Ultimately, because the first venting space (VS1) is separated to correspond to each battery assembly 100, thermal runaway transitions between the battery assemblies 100 are minimized, preventing the explosion and structural collapse of the battery pack. The gas shield 1600 may be positioned at the location corresponding to the aforementioned vertical beam 1800.

[0149] Figure 37 is a perspective view of a bottom frame according to one embodiment of the present invention, with a portion of the inner frame removed. Figure 38 is a perspective view of an outer frame and routing plate according to one embodiment of the present invention. Figure 39(a) is a partial view showing an outer frame hole, and Figure 39(b) is a partial view showing a venting device connected to an outer frame hole. Figure 40 is a plan view of a bottom frame according to one embodiment of the present invention, with the entire inner frame removed. Specifically, of the bottom frame, excluding the inner frame, the outer frame 1210, routing plate 1700, and vent plate 223 are shown in Figure 40.

[0150] Referring to Figures 31, 32, and 37-40, a venting channel that bends multiple times is formed inside the protrusion 1222. The battery pack 1000 may also include a venting device 1900 provided on the pack frame 1100. The venting device 1900 may be located inside the protrusion 1222. The venting device 1900 may be located on the lower surface of the bottom frame 1200. The venting device 1900 may be located on the lower surface of the outer frame 1210. The venting gas (VG) that flows along the venting space (VS) is finally discharged to the outside of the battery pack 1000 via the venting device 1900. As an example, an outer frame hole 1210H may be formed in the outer frame 1210, and the venting device 1900 may be mounted in such an outer frame hole 1210H. The term venting device 1900 is a general term for members and mechanisms provided to discharge venting gas and the like. For example, the venting device 1900 may be a valve structure that opens or bursts when the internal pressure exceeds a predetermined value.

[0151] The venting device 1900 may be positioned on the underside of the bottom frame 1200. Because the venting device 1900 is positioned on the underside of the bottom frame 1200, the venting gas can be discharged downwards from the battery pack 1000. The battery pack 1000 according to this embodiment can be mounted on a vehicle device, and as described above, because the venting device 1900 is positioned on the underside of the bottom frame 1200, the venting gas is discharged downwards without affecting the vehicle driver or vehicle components. Therefore, it is possible to prevent additional thermal events on the vehicle side caused by the venting gas.

[0152] Venting gas discharged from the battery cell 110 can move to the venting space (VS) of the bottom frame 1200 via the cell vent section 300V of the cell frame 300. For example, venting gas discharged from the battery cell 110 can pass through the cell vent section 300V and the vent plate 223 and move to the first venting space (VS1). Venting gas (VG) that has flowed into the first venting space (VS1) can move to the second venting space (VS2) via the filtration hole 1220H of the inner frame 1220. Venting gas that has moved to the second venting space (VS2) can be discharged to the outside of the battery pack 1000 via the venting device 1900 provided in the second venting space (VS2).

[0153] For example, the venting gas (VG) can flow from the second venting space (VS2), which is the internal space of the protrusion 1222, along a venting channel that bends multiple times, and then be discharged through the venting device 1900. There are no particular restrictions on the structure for realizing the venting channel that bends multiple times. While the venting gas (VG) flows along the venting channel that has been bent multiple times and become elongated, the temperature of the venting gas (VG) and particles decreases. Therefore, it is possible to prevent explosions from being caused by the venting gas (VG) and particles.

[0154] The following describes an example structure that forms a venting channel with multiple bends.

[0155] A routing plate 1700 may be positioned inside the protrusion 1222 of the inner frame 1220, i.e., in the second venting space (VS2). The routing plate 1700 may be a structure having an internal space and extending along one direction (parallel to the X-axis). The outer frame hole 1210H and the venting device 1900 may be positioned within the internal space of the routing plate 1700.

[0156] Venting gas discharged from the battery cell 110 can move into the venting space (VS) of the bottom frame 1200 via the cell vent section 300V of the cell frame 300. For example, venting gas discharged from the battery cell 110 can move into the first venting space (VS1) via the cell vent section 300V and the vent plate 223. Venting gas (VG) that flows into the first venting space (VS1) from the vent plate 223 can flow into the second venting space (VS2) via the filtration hole 1220H. Venting gas (VG) that flows into the second venting space (VS2) via the filtration hole 1220H can move from the external space of the routing plate 1700 within the second venting space (VS2) to the internal space of the routing plate 1700 within the second venting space (VS2). For example, the venting gas (VG) can bend multiple times as it moves into the internal space of the routing plate 1700, as shown in Figures 37 and 40.

[0157] In this way, by providing the routing plate 1700 inside the second venting space (VS2), the venting gas (VG) and particles flowing into the second venting space (VS2) move along the elongated venting channel, and the path bends multiple times. While the venting gas (VG) flows along the elongated path provided by the routing plate 1700, the temperature of the venting gas (VG) and particles decreases. Therefore, it is possible to prevent the venting gas (VG) and particles from causing an explosion. In addition, the elongated path of the venting gas (VG) prevents oxygen flowing in from outside the battery pack 1000 from coming into contact with the venting gas, etc., thus preventing an explosion. Furthermore, larger particles can be filtered out by the elongated path.

[0158] On the other hand, the external spaces of the routing plate 1700 within the second venting space (VS2) can communicate with each other. For example, the height of the routing plate 1700 is lower than the height of the protrusion 1222 of the inner frame 1220. As a result, both areas of the second venting space (VS2) located on either side of the routing plate 1700 can communicate with each other.

[0159] Figure 41 is a partial cross-sectional view showing a portion of the cross-section of a battery pack according to a modified embodiment of the present invention.

[0160] Referring to Figure 41, a side venting space (VS3) may be provided in the side frame 1300, which communicates with the venting space (VS). The venting gas (VG) that flows into the venting space (VS) of the bottom frame 1200 flows along the venting space (VS), moves to the side venting space (VS3) inside the side frame 1300, and can finally be discharged to the outside of the battery pack 1000. The side venting space (VS3) is provided inside the side frame 1300 of the pack frame 1100, and the side venting space (VS3) can communicate with the venting space (VS) of the bottom frame 1200.

[0161] Furthermore, a venting device 1900 is provided on the outer surface of the side frame 1300, and the venting device 1900 is connected to the side venting space (VS3). As a result, the venting gas (VG) in the side venting space (VS3) can be discharged to the outside of the battery pack via this venting device 1900.

[0162] For example, the venting space (VS) of the bottom frame 1200 can include a first venting space (VS1) and a second venting space (VS2). The explanation of the first venting space (VS1) and the second venting space (VS2) will be omitted as it will be redundant with what has been explained earlier. The second venting space (VS2) can communicate with the side venting space (VS3) inside the side frame 1300. If necessary, the pack frame 1100 may be provided with a connecting venting space (VS4) that connects the venting space (VS) of the bottom frame 1200 and the side venting space (VS3) of the side frame 1300. The connecting venting space (VS4) can communicate with the second venting space (VS2).

[0163] As one example, venting gas (VG) discharged from the battery cell 110 can move to the venting space (VS) of the bottom frame 1200 via the cell vent section 300V of the cell frame 300. For example, venting gas (VG) discharged from the battery cell 110 can move to the first venting space (VS1) via the cell vent section 300V. Venting gas (VG) that has flowed into the first venting space (VS1) can flow into the second venting space (VS2) via the filtration hole 1220H (see Figure 36). Venting gas (VG) that has flowed into the second venting space (VS2) can move to the side venting space (VS3) inside the side frame 1300. As described above, venting gas (VG) can move to the side venting space (VS3) via a connecting venting space (VS4) provided as needed. The venting gas (VG) that flows into the side venting space (VS3) can be discharged to the outside of the battery pack via the venting device 1900.

[0164] In this embodiment, terms indicating directions such as front, back, left, right, up, and down were used, but such terms are for convenience of explanation and may differ depending on the position of the object being examined, the position of the observer, etc.

[0165] One or more battery assemblies according to the aforementioned embodiment can be mounted together with various control and protection systems such as a Battery Management System (BMS), Battery Disconnect Unit (BDU), and cooling system to form a battery pack.

[0166] The aforementioned battery assemblies and battery packs can be applied to a variety of devices. Specifically, they can be applied to means of transportation such as electric bicycles, electric vehicles, and hybrids, as well as ESS (Energy Storage Systems), but are not limited to these, and can be applied to various devices that can use secondary batteries.

[0167] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art that utilize the basic concepts of the present invention as defined in the following claims also fall within the scope of the present invention. [Explanation of Symbols]

[0168] 100 Battery Assembly 110 battery cells 200 Cell Assembly Frame 300 Cell Frame 300V Cell Vent Section 400 Heatsink 410 Cooling Plate 500 Pad component 1000 Battery Pack 1100 Pack Frame 1200 Bottom Frame 1300 Side frame 1400 Pack Cover

Claims

1. It is a battery pack, A battery assembly containing multiple battery cells, A pack frame housing at least one of the aforementioned battery assemblies, The aforementioned pack frame is The battery assembly is placed on a bottom frame, which includes a venting space, The aforementioned battery assembly is Battery cells stacked in one direction, The cell frame includes, which extends along the periphery of the battery cell and covers the periphery of the battery cell, A battery pack in which a cell vent is formed in the portion of the cell frame that faces the bottom frame.

2. The battery pack according to claim 1, wherein the cell vent portion is arranged to correspond to the vent space.

3. The aforementioned cell frame is A first frame covering the lower end of the battery cell, A second frame covering the upper end of the battery cell, It includes a third frame and a fourth frame that cover both ends of the battery cell between the lower end and the upper end, respectively. The battery pack according to claim 1, wherein the cell vent portion is formed in the first frame.

4. Each of the aforementioned battery cells is provided with the aforementioned cell frame. The battery pack according to claim 1, wherein the battery cell and the cell frame correspond to each other in a one-to-one manner.

5. The battery pack according to claim 1, wherein the cell vent portion is in communication with the vent space of the bottom frame while venting gas is discharged from the battery cell.

6. The battery pack according to claim 1, wherein the cell vent portion protrudes toward the bottom frame and is inserted toward the venting space inside the bottom frame.

7. The aforementioned battery assembly is Includes a cell assembly frame that houses the aforementioned battery cells, The aforementioned cell assembly frame is An upper frame that covers the top of the aforementioned battery cell, The battery pack according to claim 1, further comprising a lower frame that covers the lower part of the battery cell.

8. The battery pack according to claim 1, wherein a vent cover portion that is opened at a predetermined pressure or higher is located below the cell vent portion.

9. The battery pack according to claim 8, wherein the vent cover portion covers the cell vent portion.

10. The battery pack according to claim 8, wherein the vent cover portion protrudes toward the bottom frame and is inserted toward the venting space of the bottom frame.

11. The bottom frame includes an outer frame and an inner frame, The outer frame is positioned below the inner frame. The battery pack according to claim 1, wherein the venting space is provided by the outer frame and the inner frame.

12. The aforementioned venting spaces are provided in multiple locations. The battery pack according to claim 11, wherein the venting gas generated from the battery cell passes sequentially through the venting space.

13. The inner frame includes recesses and protrusions, The venting space includes a first venting space provided in the recess and a second venting space provided in the protrusion. The battery pack according to claim 11, wherein the inner frame has a filtration hole that connects the first venting space and the second venting space.

14. The battery pack according to claim 13, wherein a venting channel that is bent multiple times is formed inside the protrusion.

15. The battery pack according to claim 13, wherein a venting device that opens or ruptures when the pressure exceeds a predetermined level is provided inside the protrusion.

16. The battery pack according to claim 1, further comprising a heatsink having at least one cooling plate, positioned between at least one of the battery cells.

17. The battery pack according to claim 16, wherein a refrigerant flows inside the cooling plate.

18. The battery pack according to claim 16, wherein the battery cell and the cooling plate are in surface contact.

19. The battery pack according to claim 1, further comprising at least one pad member disposed between at least one of the battery cells.

20. The pack frame includes a side frame that extends along the periphery of the bottom frame, The side frame is provided with a side venting space that communicates with the venting space. The battery pack according to claim 1, wherein the venting gas that flows into the venting space of the bottom frame moves to the side venting space.

21. A device comprising a battery pack according to any one of claims 1 to 20.

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