Battery pack and device including same

Abstract

A battery pack according to an embodiment of the present invention comprises: a plurality of battery cells stacked along one direction; cell frames extending along the edges of the battery cells and covering the edges of the battery cells; and a pack frame in which the battery cells are housed. The battery cells are directly mounted to the pack frame in a state in which the edges of the battery cells are covered by the cell frames.

Description

Battery pack and device including same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0069318, filed May 28, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a battery pack and a device including the same, and more particularly, to a battery pack and a device including the same that can minimize thermal runaway transition, prevent structural collapse, and increase space utilization.

[0004] In modern society, the widespread use of portable devices like cell phones, laptops, camcorders, and digital cameras has fueled active development of technologies related to these devices. Furthermore, rechargeable secondary batteries are increasingly being used as power sources for electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (P-HEVs) to address air pollution caused by conventional gasoline-powered vehicles. This, in turn, heightens the need for further development of these batteries.

[0005] Currently commercialized secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based secondary batteries.

[0006] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. The lithium secondary battery comprises an electrode assembly comprising a positive electrode plate and a negative electrode plate, each coated with the positive and negative electrode active materials, with a separator interposed between them, and a battery case that seals and houses the electrode assembly together with an electrolyte.

[0007] In general, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0008] In the case of secondary batteries used in small devices, 2-3 battery cells are arranged, but in the case of secondary batteries used in medium to large devices such as automobiles, battery modules in which multiple battery cells are electrically connected have been conventionally used. Such battery modules have improved capacity and output by forming a battery cell stack by connecting multiple battery cells in series or parallel. One or more battery modules can be mounted 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.

[0009] That is, in the case of a conventional battery pack, a battery module is included as a sub-concept, and a battery module includes battery cells as a sub-concept. Furthermore, 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 or capacity of the battery pack required for the electric vehicle.

[0010] However, these conventional battery pack models suffer from poor space utilization. This is because the battery pack is constructed by forming battery modules with battery cells and mounting these modules to a pack frame. Therefore, there is a need to develop a battery pack structure that can improve space utilization and ultimately energy density.

[0011] Meanwhile, the most important requirements in recent battery modules and battery packs are quick charge and thermal propagation control.

[0012] First, one of the challenges of rapid charging is the heat generated during rapid charging. Therefore, a cooling system is essential to manage the heat generated during rapid charging to an appropriate level. Conventional battery modules utilize an edge-cooling structure that cools only one side (usually the bottom) of the battery cells. Applying rapid charging to an edge-cooled battery module increases the temperature difference between the top and bottom, and the top, with its limited cooling effect, inevitably reduces rapid charging efficiency. Therefore, ensuring effective cooling performance is crucial for rapid charging.

[0013] Next, with regard to thermal propagation control, when a thermal event occurs in one of the multiple battery cells included in a battery pack, it is necessary to block the thermal propagation of such thermal event to other battery cells.

[0014] If heat transfer between battery cells is not properly controlled, this can lead to thermal events in other battery cells within the pack, potentially leading to more serious problems such as fire or explosion within the pack. Furthermore, fire or explosions occurring within the pack can cause significant damage to people and property in the surrounding area. Therefore, these battery packs require a configuration capable of appropriately controlling the aforementioned thermal events and their propagation.

[0015] In summary, there is a growing demand for battery packs that have effective cooling means for rapid charging, as well as means to suppress heat transfer between battery cells, and that can improve energy density by increasing internal space utilization.

[0016] The problem to be solved by the present invention is to provide a battery pack having an effective cooling means for rapid charging and a means for suppressing heat transfer between battery cells, and having improved internal space utilization, and a device including the same.

[0017] However, the problems to be solved by the embodiments of the present invention are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0018] A battery pack according to one embodiment of the present invention comprises: a plurality of battery cells stacked along one direction; cell frames extending along edges of the battery cells and covering the edges of the battery cells; and a pack frame in which the battery cells are accommodated. The battery cells are directly mounted to the pack frame with the edges of the battery cells covered by the cell frames.

[0019] One of the above cell frames may cover the edges of a plurality of the above battery cells. The plurality of the above battery cells covered by one of the above cell frames may be positioned along a longitudinal direction, and the longitudinal direction may be a direction parallel to a direction in which an electrode lead protrudes from the above battery cells.

[0020] The cell frame may include a first frame covering the lower portion of the battery cells; a third frame covering one end of one of the battery cells; and a fourth frame covering one end of another of the battery cells.

[0021] Among the cell frames, a portion corresponding to the upper portion of the battery cells may be opened, and a thermal resin layer formed by applying thermal resin to the upper portion of the battery cells may be positioned, and the upper portion of the battery cells may be in contact with the thermal resin layer.

[0022] The cell frame may include a first frame covering the lower portion of the battery cell; and a third frame and a fourth frame covering both ends of the battery cell, respectively.

[0023] The above cell frame may include a second frame covering the upper portion of the battery cell.

[0024] A cell vent portion may be formed in a portion of the cell frame corresponding to the lower portion of the battery cell.

[0025] The pack frame may include a bottom frame on which the battery cells are placed and a venting space is provided, and while venting gas is discharged from the battery cells, the cell vent portion may be in communication with the venting space of the bottom frame.

[0026] An adhesive material may be attached to a portion of the lower portion of the above battery cell, excluding a portion corresponding to the cell vent.

[0027] The battery cell may include an electrode assembly and a pouch case for storing the electrode assembly. The lower portion of the battery cell may be a sealing portion formed by sealing an end of the pouch case.

[0028] As the adjacent cell frames are joined together, the battery cells located therein can be fixed.

[0029] At least one cooling plate may be placed at least one location between the above battery cells.

[0030] A thermal resin layer formed by applying thermal resin to the upper portion of the above battery cells may be positioned, and the upper portion of the cooling plate may be in contact with the thermal resin layer.

[0031] The above battery cells may be stacked along the above direction to form a battery cell stack. The pack frame may include a bottom frame on which the battery cell stack is placed and a side frame extending upward from one end of the bottom frame. The side frame may be positioned on one side of the battery cell stack, and a BMS frame on which a BMS (Battery Management System) module is mounted may be positioned on the other side opposite to the one side of the battery cell stack.

[0032] The above side frame and the BMS frame can pressurize the one side and the other side of the battery cell stack, respectively.

[0033] A device according to one embodiment of the present invention includes the battery pack.

[0034] According to embodiments of the present invention, surface cooling of the battery cells can be achieved by a cell frame covering the edges of the battery cells and a cooling plate disposed between the battery cells, thereby improving cooling performance.

[0035] Additionally, when a thermal event occurs in a battery cell, high-temperature venting gases or particles emitted from the cell travel along a specific, intended path through the cell vents provided in the cell frame. This minimizes the spread of a thermal event occurring in a specific battery cell to other battery cells.

[0036] In addition, since the battery cells are directly mounted on the pack frame with the edges of the battery cells covered by the cell frame, the packing structure can be minimized, so that the space utilization and energy density of the battery pack can be improved.

[0037] The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

[0038] Figure 1 is a perspective view showing a battery pack according to one embodiment of the present invention.

[0039] FIG. 2 is a perspective view showing one of the battery cell units included in the battery pack of FIG. 1.

[0040] Fig. 3 is a perspective view showing the battery cell unit of Fig. 2 in a state where some battery cells and cooling plates are separated.

[0041] FIG. 4 is a perspective view showing battery cells and a cell frame according to one embodiment of the present invention.

[0042] Figure 5 is an exploded perspective view of the battery cells and cell frame of Figure 4.

[0043] Figure 6 is a perspective view showing a battery cell according to one embodiment of the present invention.

[0044] Figures 7 (a) and (b) are cross-sectional perspective views of battery cells coupled to a cell frame, respectively.

[0045] Figure 8 is a cross-sectional perspective view of a battery cell coupled to a cell frame.

[0046] Figure 9 is a perspective view showing a cell frame according to one embodiment of the present invention.

[0047] Figure 10 is a perspective view showing a state in which two cell frames are combined.

[0048] Fig. 11 is a perspective view showing a battery cell unit according to another embodiment of the present invention.

[0049] Fig. 12 is a perspective view showing the battery cell unit of Fig. 11 in a state where some battery cells and cooling plates are separated.

[0050] FIG. 13 is a perspective view showing some of the battery cells and cell frames included in the battery cell unit of FIG. 11.

[0051] Figure 14 is an exploded perspective view of the battery cells and cell frame of Figure 13.

[0052] FIG. 15 is an exploded perspective view of battery cells and cell frames according to another embodiment of the present invention.

[0053] Fig. 16 is a perspective view showing a battery cell unit and a thermal resin layer together according to one embodiment of the present invention.

[0054] Fig. 17 is a cross-sectional view showing a cross-section taken along the cutting line AA of Fig. 16.

[0055] Fig. 18 is a perspective view showing a heat sink and a thermal resin layer according to one embodiment of the present invention.

[0056] FIG. 19 is a perspective view showing a heat sink and pad member according to one embodiment of the present invention.

[0057] Figure 20 is a front view showing the heat sink and pad member of Figure 19.

[0058] Figure 21 is a front view showing the heat sink, pad member and some cell frames.

[0059] Figure 22 is a perspective view of a battery cell unit viewed from below according to one embodiment of the present invention.

[0060] Figure 23 is a perspective view showing a pack frame included in a battery pack according to one embodiment of the present invention.

[0061] Fig. 24 is a perspective view showing the floor frame and side frame included in the pack frame of Fig. 23.

[0062] Figure 25 is a cross-sectional perspective view taken along the cutting line BB of Figure 24.

[0063] Fig. 26 is a perspective view showing a BMS frame included in the pack frame of Fig. 23.

[0064] Figures 27 and 28 are drawings for explaining a method of arranging battery cell units in a pack frame.

[0065] Figure 29 is a perspective view showing a pack frame according to another embodiment of the present invention.

[0066] Fig. 30 is a perspective view showing a floor frame included in the pack frame of Fig. 29.

[0067] Figure 31 is a perspective view showing the inner frame and cover plates included in the bottom frame of Figure 30.

[0068] Figure 32 is a partial drawing showing an enlarged portion of the “C” portion of Figure 31.

[0069] Fig. 33 is a perspective view of the bottom frame of Fig. 30, showing a portion of the inner frame removed.

[0070] Figure 34 is a perspective view showing the outer frame and routing plates in the bottom frame of Figure 30.

[0071] Figure 35 (a) is a partial drawing showing an outer frame hole, and Figure 35 (b) is a partial drawing showing a venting device coupled to the outer frame hole.

[0072] Figure 36 is a partial cross-sectional view of a battery pack according to one embodiment of the present invention.

[0073] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0074] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0075] Furthermore, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the present invention is not necessarily limited to the illustrated components. In the drawings, the thicknesses are enlarged to clearly represent various layers and regions. Furthermore, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0076] Furthermore, when we say that a layer, membrane, region, plate, or other part is "on" or "over" another part, this includes not only cases where it is "directly on" the other part, but also cases where there are other parts in between. Conversely, when we say that a part is "directly on" another part, it means that there are no other parts in between. Furthermore, saying that a part is "on" or "over" a reference part means that it is located above or below the reference part, and does not necessarily mean that it is located "above" or "over" the direction opposite to gravity.

[0077] Additionally, throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0078] Additionally, throughout the specification, when we say "in plan", we mean when the target portion is viewed from above, and when we say "in cross section", we mean when the target portion is viewed from the side in a cross-section cut vertically.

[0079] Fig. 1 is a perspective view illustrating a battery pack according to one embodiment of the present invention. Fig. 2 is a perspective view illustrating one of the battery cell units included in the battery pack of Fig. 1.

[0080] Referring to FIGS. 1 and 2, a battery pack (1000) according to one embodiment of the present invention includes: a plurality of battery cells (110) stacked along one direction; cell frames (300) extending along edges of the battery cells (110) and covering the edges of the battery cells (110); and a pack frame (1100) in which the battery cells (110) are accommodated. The battery cells (110) are directly mounted on the pack frame (1100) with the edges of the battery cells (110) covered by the cell frames (300).

[0081] Specifically, the battery cells (110) may be stacked along one direction while each of the battery cells (110) is covered by a cell frame (300), thereby forming a battery cell stack (120). That is, a cell frame (300) may be provided for each of the battery cells (110). For example, the battery cells (110) may be stacked along a direction parallel to the X-axis while each of the battery cells (110) is covered by a cell frame (300), thereby forming a battery cell stack (120). The detailed structure of the cell frame (300) will be described later.

[0082] In addition, some of the battery cells (110) covered by the cell frame (300) may form a battery cell unit (100). The battery cells (110) may be mounted as units of battery cell units (100) on the pack frame (1100). In other words, some of the battery cells (110) may be gathered to form a battery cell unit (100), and these battery cell units (100) may be gathered to form a battery cell stack (120). In this specification, a unit in which some of the battery cells (110) are gathered is referred to as a battery cell unit (100), and the entirety of the battery cells (110) stacked inside the battery pack (1000) is referred to as a battery cell stack (120).

[0083] FIG. 3 is a perspective view showing some battery cells and cooling plates separated from the battery cell unit of FIG. 2. FIG. 4 is a perspective view showing battery cells and a cell frame according to an embodiment of the present invention. FIG. 5 is an exploded perspective view of the battery cells and the cell frame of FIG. 4. FIG. 6 is a perspective view showing a battery cell according to an embodiment of the present invention.

[0084] Referring to FIGS. 3 to 6, the battery cell (110) according to the present embodiment may be a battery cell of various shapes. For example, as illustrated in FIGS. 4 to 6, the battery cell (110) according to the present embodiment may be a pouch-type battery cell. Hereinafter, a pouch-type battery cell will be described, but the battery cell (110) according to the present embodiment is not limited thereto, and various types of battery cells may be applied.

[0085] The battery cell (110) according to the present embodiment may be in the form of an electrode assembly having electrode leads (111) protruding in one or both directions, housed in a pouch case (114). This battery cell (110) may have a rectangular sheet shape. The battery cell (110) may have a lower portion (114a), an upper portion (114b), and both ends (114c, 114d).

[0086] The battery cell (110) can be formed by housing an electrode assembly in a pouch case (114) of a laminate sheet including a resin layer and a metal layer, and then bonding the outer periphery of the pouch case (114). For example, the battery cell (110) can 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. As another embodiment, a structure in which all electrode leads (111) of the battery cell (110) protrude in one direction is also possible. One of the electrode leads (111) is a positive electrode lead, and the other is a negative electrode lead.

[0087] The battery cell (110) can be manufactured by bonding the two ends (114c, 114d) of the pouch case (114) and the lower end (114a) connecting them while the electrode assembly (not shown) is stored 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), and the sealing portions (114s) have a structure in which they are sealed by a method such as fusion, and the remaining upper end (114b) can be formed as a folding portion. That is, the battery cell (110) according to the present embodiment can be a pouch-type secondary battery in which the electrode assembly is stored inside the pouch case (114) and the outer periphery of the pouch case (114) is sealed to form the sealing portion (114s). In Fig. 6, only the sealing portions (114s) formed at both ends (114c, 114d) of the pouch case (114) are shown, 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 completed for space utilization. This will be explained again in Fig. 8.

[0088] The pouch case (114) of the laminate sheet may include an inner resin layer for sealing, a metal layer for preventing penetration of materials, and an outermost outer resin layer. Based on the electrode assembly inside the pouch case (114), the inner resin layer may be positioned at the innermost side, the outer resin layer may be positioned at the outermost side, and the metal layer may be positioned between the inner resin layer and the outer resin layer.

[0089] The outer resin layer may have excellent tensile strength and weather resistance relative to its thickness and may exhibit electrical insulation properties to protect the electrode assembly from the outside. The outer resin layer may include polyethylene terephthalate (PET) resin or nylon resin. The metal layer may prevent air, moisture, etc. from entering the pouch-type secondary battery. The metal layer may include aluminum (Al). The inner resin layers may be thermally bonded to each other by heat and / or pressure applied while the electrode assembly is embedded. The inner resin layer may include cast polypropylene (CPP) or polypropylene (PP).

[0090] A pouch case (114) may be divided into two parts, and a concave receiving portion in which an electrode assembly can be mounted may be formed in at least one of the two parts. Along the outer periphery of the receiving portion, the inner resin layers of the two parts of the pouch case (114) may be bonded to each other to form a sealing portion (114s). In this manner, the pouch case may be sealed, and a battery cell (110), which is a pouch-type secondary battery, may be manufactured.

[0091] Meanwhile, referring to Fig. 6, the sealing portion (114s) at both ends (114c, 114d) of the battery cell (110) where the electrode lead (111) protrudes from the battery cell (110) corresponds to the so-called terrace portion of the battery cell (110). This terrace portion is thinner than the cell body (113) of the battery cell (110).

[0092] As described above, some of the battery cells (110) covered by the cell frame (300) may form a battery cell unit (100). For example, a plurality of battery cells (110) may be stacked along one direction so as to be electrically connected to each other to form a battery cell unit (100). For example, a plurality of battery cells (110) may be stacked along a direction parallel to the X-axis while standing upright. Accordingly, the electrode leads (111) may protrude in a direction perpendicular to the direction in which the battery cells (110) are stacked. In the battery cell (110), one electrode lead (111) may protrude toward the Y-axis direction, and the other electrode lead (111) may protrude toward the -Y-axis direction. If the electrode leads (111) are battery cells that protrude only in one direction, the electrode leads (111) may protrude in the Y-axis direction or the -Y-axis direction.

[0093] Each of (a) and (b) of FIG. 7 is a cross-sectional perspective view of a battery cell coupled to a cell frame. Each of FIG. 8 is a cross-sectional perspective view of a battery cell coupled to a cell frame. Specifically, each of FIG. 7 (a) and (b) is a cross-sectional perspective view of the battery cells coupled to the cell frame, which is obtained by cutting along the xy plane and then enlarging both ends thereof, and FIG. 8 is a cross-sectional perspective view of the battery cells coupled to the cell frame, which is obtained by cutting along the xz plane. FIG. 9 is a perspective view showing a cell frame according to an embodiment of the present invention. FIG. 10 is a perspective view showing a state in which two cell frames are coupled.

[0094] Referring to FIGS. 4 to 10 together, the cell frame (300) according to the present embodiment may extend along the edge of the battery cell (110) and cover the edge of the battery cell (110). One cell frame (300) may cover the edges of a plurality of battery cells (110). The plurality of battery cells (110) covered by one cell frame (300) may be positioned along the longitudinal direction, wherein the longitudinal direction may be a direction parallel to the direction in which the electrode lead (111) protrudes from the battery cell (110). That is, the battery cells (110) positioned within one cell frame (300) may be positioned along the Y-axis direction, which is a direction parallel to the direction in which the electrode lead (111) protrudes. There is no particular limitation on the number of battery cells (110) positioned within one cell frame (300). For example, FIGS. 4 and 5 illustrate that one cell frame (300) covers two battery cells (110).

[0095] Specifically, the cell frame (300) may include a first frame (310) covering the lower portion (114a) of the battery cells (110); a third frame (330) covering one end (114c) of one of the battery cells (110); and a fourth frame (340) covering one end (114d) of the other of the battery cells (110). Unlike the cell frame described later in FIG. 15, the cell frame (300) according to the present embodiment may have an open upper portion without a portion covering the upper portion (114b) of the battery cell (110). That is, the cell frame (300) may have a portion that corresponds to the upper portion (114b) of the battery cell (110) open.

[0096] Meanwhile, a cell vent part (300V) may be formed in a portion corresponding to the lower portion (114a) of the battery cell (110) among the cell frames (300). The cell vent part (300V) may be formed in the first frame (310) among the cell frames (300). Specifically, the cell vent part (300V) may be a portion that guides the discharge of high-temperature venting gas or particles generated from the battery cell (110) when a thermal event or thermal runaway occurs in any one of the battery cells (110). This cell vent part (300V) may be provided in a portion corresponding to the central portion of each battery cell (110) among the first frame (310) that covers the lower portion (114a) of the battery cell (110). For example, in FIG. 5, two cell vent parts (300V) are provided in the first frame (310). One of the two cell vent parts (300V) may be provided in a portion corresponding to the central portion of one battery cell (110), and the other of the two cell vent parts (300V) may be provided in a portion corresponding to the central portion of another battery cell (110).

[0097] For example, the cell vent part (300V) may include a first part (300V1), a second part (300V2), and a third part (300V3). The first part (300V1), the second part (300V2), and the third part (300V3) may extend downward, forming an open space therebetween. However, this is only one exemplary structure of the cell vent part (300V), and it is sufficient as long as it can guide the discharge of high-temperature venting gas or particles generated from the battery cell (110) in an open form, and there are no other limitations on its form.

[0098] The portion of the first frame (310) excluding the cell vent portion (300V) is in close contact with the lower portion (114a) of the battery cell (110), but the portion corresponding to the cell vent portion (300V) is perforated downward, so that high-temperature venting gas or particles generated from the battery cell (110) can be discharged downward through the cell vent portion (300V). That is, the battery module according to the present embodiment has a directional venting structure that discharges venting gas and particles, etc. in a preset 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 portion (114a) of the battery cell (110), a so-called “lower venting” structure in which venting gas and particles, etc. are discharged downward can be implemented. The advantages of the “lower venting” structure will be explained again below.

[0099] Meanwhile, referring to FIGS. 4 to 8, an adhesive member (130) may be attached to a portion of the lower portion (114a) of the battery cell (110) except for a portion corresponding to the cell vent portion (300V). As described above, the lower portion (114a) of the battery cell (110) may be a sealing portion (114s, see FIGS. 6 and 8) where the pouch case (114) is sealed, and the upper portion (114b) of the battery cell (110) may not be a sealing portion but may be a folding portion where the pouch case (114) is folded. In other words, the battery cell (110) may include an electrode assembly (not shown) and a pouch case (114) that accommodates the electrode assembly, and the lower portion (114a) of the battery cell (110) may be a sealing portion (114s) formed by sealing an end of the pouch case (114).

[0100] When a thermal event or thermal runaway occurs in a battery cell (110), venting gas is generated in the battery cell (110) and the internal pressure of the battery cell (110) increases. This venting gas can be mainly discharged through the sealing portion (114s) of the battery cell (110). That is, due to the increased internal pressure, the sealing in some portions of the sealing portion (114s) is released, and the venting gas, etc. can burst and be discharged through the released portion of the sealing portion (114s).

[0101] According to the present embodiment, the battery cell (110) can be arranged so that the lower portion (114a) of the battery cell (110) becomes the sealing portion (114s) and the upper portion (114b) of the battery cell (110) becomes the folding portion. Through this arrangement, the “lower venting” structure that discharges venting gas and particles generated from the battery cell (110) downward can be more clearly implemented. FIG. 8 shows the sealing portion (114s) corresponding to the lower portion (114a) of the battery cell (110) folded for space utilization after sealing is completed.

[0102] Meanwhile, it is preferable that the venting gas of the battery cell (110) be discharged through the cell vent portion (300V) of the cell frame (300), among the lower directions. To this end, an adhesive member (130) may be attached to a portion of the lower portion (114a) of the battery cell (110) except for the portion corresponding to the cell vent portion (300V). The adhesive member (130) may be, for example, an adhesive tape.

[0103] The portion of the lower part (114a) of the battery cell (110) to which the adhesive member (130) is attached is not sealed even if the internal pressure of the battery cell (110) increases because the degree of sealing is supplemented by the adhesive member (130). On the other hand, the portion of the lower part (114a) of the battery cell (110) to which the adhesive member (130) is not attached has a relatively low degree of sealing, so the sealing may be released before the portion to which the adhesive member (130) is attached. Accordingly, the venting gas may be discharged to the portion corresponding to the cell vent part (300V) of the lower part (114a) of the battery cell (110) (i.e., the portion without the adhesive member), and the venting gas may be discharged downward through the cell vent part (300V).

[0104] Referring again to FIGS. 3, 4, 5, 9, and 10, in the battery cell unit (100) according to the present embodiment, adjacent cell frames (300) may be coupled to each other, and battery cells (110) located therein may be fixed. There is no particular limitation on the coupling method between the cell frames (300), but coupling may be achieved by physical restraint. For example, each cell frame (300) may include a hook protrusion (300P) and a hook groove (300G). The hook protrusion (300P) may protrude in the direction in which another adjacent cell frame (300) is located. The cell frames (300) may be coupled to each other in such a manner that the hook protrusion (300P) of one cell frame (300) is hook-coupled to the hook groove (300G) of another adjacent cell frame (300). An example of such a hook coupling between two cell frames (300) is illustrated in FIG. 10. As the connection between the hook protrusion (300P) and the hook groove (300G) is continuously performed for each adjacent cell frame (300), a plurality of cell frames (300) can all be connected.

[0105] Each battery cell (110) is covered by each cell frame (300), and a battery cell unit (100) can be formed by combining these cell frames (300). In this way, the battery cell unit (100) including the cell frames (300) is structurally more stable and can withstand external vibrations or shocks better than a form in which only the battery cells (110) are stacked without the cell frames (300). In the case in which only the battery cells (110) are stacked without the cell frames (300), there may be a problem in that the battery cell stack cannot be maintained by external vibrations or shocks and the shape collapses. In addition, in the case of the battery cell unit (100) or the battery cell stack (120) including the cell frames (300), since it is assembled in units of cell frames (300), replacement can be easily performed in units of cell frames (300). That is, even after the battery cell unit (100) or battery cell stack (120) has already been manufactured, there is an advantage in that a specific battery cell (110) in which a problem has occurred can be easily replaced by disassembling and reassembling the cell frame (300).

[0106]

[0107] Fig. 11 is a perspective view showing a battery cell unit according to another embodiment of the present invention. Fig. 12 is a perspective view showing some of the battery cells and cooling plates in the battery cell unit of Fig. 11 separated. Fig. 13 is a perspective view showing some of the battery cells and cell frames included in the battery cell unit of Fig. 11. Fig. 14 is an exploded perspective view of the battery cells and cell frames of Fig. 13.

[0108] Referring to FIGS. 11 to 14, a battery cell unit (100) according to another embodiment of the present invention may include battery cells (110) and cell frames (300) that extend along the edges of the battery cells (110) and cover the edges of the battery cells (110). Unlike the embodiment of FIGS. 2 to 10 in which a plurality of battery cells (110) are mounted on a single cell frame (300) described above, the cell frame (300) according to the present embodiment may cover only the edge of a single battery cell (110).

[0109] Specifically, the cell frame (300) according to the present embodiment may include a first frame (310) covering the lower end (114a) of the battery cell (110); and a third frame (330) and a fourth frame (340) covering the opposite ends (114c, 114d) of the battery cell (110), respectively. In the present embodiment, the battery cells (110) and the cell frames (300) correspond one-to-one, and each of the battery cells (110) may be covered by each of the cell frames (300). Unlike the cell frame described later in FIG. 15, the cell frame (300) according to the present embodiment may have an open upper portion without a portion covering the upper end (114b) of the battery cell (110). That is, the cell frame (300) may have a portion that corresponds to the upper end (114b) of the battery cell (110) open.

[0110] In addition, the fact that a cell vent part (300V) is formed in the first frame (310) of the cell frame (300) and that an adhesive member (130) is attached to a portion of the lower part (114a) of the battery cell (110) except for the portion corresponding to the cell vent part (300V) is the same as or similar to the previously described embodiment, so a detailed description thereof is omitted.

[0111] In addition, in the battery cell unit (100), when adjacent cell frames (300) are coupled to each other, the battery cells (110) located therein can be fixed. There is no particular limitation on the coupling method between the cell frames (300), but coupling may be achieved according to physical restraint. For example, each cell frame (300) may include a hook protrusion (300P) and a hook groove (300G). Since the specific description of the hook protrusion (300P) and the hook groove (300G) is the same as or similar to the previously described embodiment, a detailed description thereof will be omitted.

[0112] FIG. 15 is an exploded perspective view of battery cells and cell frames according to another embodiment of the present invention.

[0113] Referring to FIG. 15, the cell frame (300) according to the present embodiment, as described above, can extend along the edge of the battery cell (110) and cover the edge of the battery cell (110). In addition, a cell vent part (300V) can be formed in a portion of the cell frame (300) corresponding to the lower end (114a) of the battery cell (110), and when adjacent cell frames (300) are coupled to each other, the battery cells (110) located therein can be fixed.

[0114] However, the cell frame (300) according to the present embodiment 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 a third frame (330) and a fourth frame (340) covering the opposite ends (114c, 114d) of the battery cell (110), respectively. That is, the cell frame (300) of FIG. 15 may include the second frame (320) covering the upper end (114b) of the battery cell (110), such that a portion of the cell frame (300) corresponding to the upper end (114b) of the battery cell (110) is not opened.

[0115]

[0116] Below, the cooling plate and thermal resin layer according to the present embodiment will be described in detail.

[0117] Fig. 16 is a perspective view showing a battery cell unit and a thermal resin layer together according to an embodiment of the present invention. Fig. 17 is a cross-sectional view taken along the cutting line AA of Fig. 16. Fig. 18 is a perspective view showing a heat sink and a thermal resin layer according to an embodiment of the present invention. Fig. 19 is a perspective view showing a heat sink and a pad member according to an embodiment of the present invention. Fig. 20 is a front view showing the heat sink and the pad member of Fig. 19. Fig. 21 is a front view showing a heat sink, a pad member, and some cell frames.

[0118] Referring to FIG. 3 and FIG. 16 to FIG. 21, at least one cooling plate (410) may be placed at at least one location between the battery cells (110). The cooling plates (410) may be configured in plurality, and in this specification, a plurality of cooling plates (410) are collectively referred to as a heat sink (400).

[0119] FIG. 3 illustrates that a cooling plate (410) is positioned adjacent to each of the battery cells (110) arranged along the longitudinal direction. FIGS. 16 to 20 also illustrate that a cooling plate (410) is positioned adjacent to each of the battery cells (110).

[0120] The cooling plate (410) according to the present embodiment may be a plate-shaped heat transfer member. Specifically, the battery cell (110) and the cooling plate (410) may be in surface contact. At least one surface of the battery cell (110) may be in surface contact with the cooling plate (410). More specifically, one surface of the cooling plate (410) may be in contact with one surface of the cell body (113, see FIG. 6) of the battery cell (110). One surface of the battery cell (110) may be in contact with the cooling plate (410), or both sides of the battery cell (110) may be in contact with the cooling plate (410). That is, at least one surface of the battery cell (110) may be in direct surface contact with the cooling plate (410).

[0121] There is no particular limitation on the material applied to the cooling plate (410) as long as it is a material with high thermal conductivity. For example, the cooling plate (410) may include a metal material, graphite material, or plastic material with excellent thermal conductivity. Among them, it may be most preferable to apply a graphite material to the cooling plate (410). The cooling plate (410) applied with a graphite material may be consistent with the design intent of the present invention because it exhibits the characteristics of high thermal conductivity, light weight, and low thermal expansion compared to other materials. Meanwhile, if the cooling plate (410) includes a metal material, insulation treatment may be performed on the surface of the cooling plate (410) as needed.

[0122] Meanwhile, according to the present embodiment, a thermal resin layer (800) formed by applying thermal resin to the upper portion of the battery cells (110) may be positioned, and the upper portion of the cooling plate (410) may be in contact with the thermal resin layer (800). The thermal resin may include a thermally conductive adhesive material, and specifically, may include at least one of a silicone material, a urethane material, or an acrylic material. The thermal resin may be in a liquid state when applied or may be hardened after application. In addition, the thermal resin layer has excellent thermal conductivity characteristics and can quickly discharge heat generated from the battery cells (110) to the upper portion of the battery module.

[0123] As described above, the cooling plate (410) can cool the battery cell (110) in a plate-like shape. The heat generated in the battery cell (110) can be discharged through the upper direction of the battery cell unit (100) or the battery cell stack (120) through the cooling plate (410) and the thermal resin layer (800) in sequence. In particular, the heat generated in the battery cell (110) can be ultimately transferred to the pack cover (1400) described below and can be cooled by the pack cover (1400). The structure of the pack cover (1400) will be described below.

[0124] Conventional battery modules have an edge cooling structure in which a thermal resin layer is brought into contact only with the edge portion of the battery cell, and the heat of the battery cell is discharged by the thermal resin layer directly / indirectly coming into contact with a heat sink. On the other hand, in the present embodiment, a cooling plate (410) having excellent thermal conductivity may be interposed between the battery cells (110) to have a surface cooling structure in which it comes into contact with one surface of the cell body (113, see FIG. 6) of the battery cells (110). Since one surface of the cell body (113, see FIG. 6) of the battery cell (110) can come into contact with one surface of the cooling plate (410), the cooling area is much wider, and thus there is an advantage of superior cooling performance compared to conventional battery modules.

[0125] Recently, quick charging is a prerequisite for battery modules, but one of the problems with quick charging is the heat generated during quick charging. A cooling system is essential for managing the heat generated during the process to an appropriate level. When quick charging is applied to a battery module with a conventional edge-cooling structure, the temperature difference between the upper and lower parts increases, and the upper part, where the cooling effect is insufficient, inevitably reduces the quick charging efficiency. On the other hand, in the battery pack according to the present embodiment, the cooling plate (410) makes surface contact with the battery cells (110) and directly cools the battery cells (110), so that it can have excellent cooling performance enough to control the heat generation during quick charging.

[0126] There is no special limitation on the number or size of the cooling plates (410) as long as surface cooling of the battery cells (110) can be performed. The number of cooling plates (410) may be appropriately changed in consideration of the size, capacity, heat generation, etc. of the battery pack (1000). In addition, there is no special limitation on the area of ​​the cooling plate (410) as long as it can cover 60% or more of the area of ​​one side of the battery cells (110). However, a plurality of cooling plates (410) may be provided within the battery cell unit (100), and it is preferable that the number of cooling plates (410) be secured so that one side of all the battery cells (110) can be in contact with the cooling plates (410).

[0127] Meanwhile, in the case of the cell frame (300) described in FIGS. 3 to 5 or the cell frame (300) described in FIGS. 12 to 14, a portion corresponding to the upper portion (114b) of the battery cell (110) may be opened. When such a cell frame (300) is applied, the upper portion (114b) of the battery cell (110) may be in contact with the thermal resin layer (800). That is, the portion of the cell frame (300) corresponding to the upper portion (114b) of the battery cell (110) is opened, and the opened upper portion (114b) of the battery cell (110) may be in contact with the thermal resin layer (800). Accordingly, edge cooling, which discharges heat through the edge portion of the battery cell, may be performed together with surface cooling by the cooling plate (410). In the present embodiment, since edge cooling and surface cooling are performed together, better cooling performance may be realized.

[0128] Meanwhile, in the case of the cell frame (300) described in FIG. 15, since the upper part (114b) of the battery cell (110) is covered by the second frame (320), it cannot come into contact with the thermal resin layer (800), and the additional edge cooling structure as described above cannot be formed. In the case of the cell frame (300) of FIG. 15, instead of giving up additional cooling performance, the battery cell (110) can be fixed more stably because all four ends (114a, 114b, 114c, 114d) of the battery cells (110) are covered.

[0129] Meanwhile, referring again to FIGS. 19 to 21, at least one pad member (500) may be placed at least in one location between the battery cells (110). The pad member (500) may be a foam-type member having thermal insulation properties. As long as the pad member (500) has thermal insulation properties and a certain degree of elasticity, there is no particular limitation on the material of the pad member (500). For example, the pad member (500) may include a silicone material or an aerogel material.

[0130] In one embodiment of the present invention, a cooling plate (410) or a pad member (500) may be positioned between battery cells (110). Specifically, in the battery cell unit (100), the battery cells (110) are stacked while being covered by cell frames (300), and either a cooling plate (410) or a pad member (500) may be positioned between adjacent battery cells (110). The battery cells (110) coupled to the cell frames (300) may be interposed in the space (S, see FIG. 20) between the cooling plates (410) and the pad members (500). FIG. 21 illustrates that each of the four cell frames (300) is interposed between the cooling plates (410) and the pad members (500). Of course, in Fig. 21, the battery cell (110) is not visible because it is covered by the cell frame (300), but the battery cell (110) is located inside the cell frame (300).

[0131]

[0132] Below, the functions of the cell frame (300), the cooling plate (410) of the heat sink (400), and the pad member (500) will be described in more detail.

[0133] Referring to FIGS. 3 to 21 together, the cell frame (300) according to the present embodiment extends along the edge of each of the battery cells (110) and covers the edges of the battery cells (110), so that one surface of the cell body (113) of the battery cell (110) is exposed without being covered by the cell frame (300). The cell frame (300) can stably fix the battery cells (110), and at the same time, guide one surface of the cell body (113) of the battery cells (110) to come into contact with the cooling plate (410) of the heat sink (400). That is, surface cooling of the battery cells (110) in the battery cell stack (120) can be implemented by the cell frame (300) and the cooling plate (410). Accordingly, the battery pack (1000) according to the present embodiment can have excellent cooling performance capable of controlling heat generation during rapid charging.

[0134] Since one side of the cell body (113) of the battery cell (110) is in close contact with the cooling plate (410) or the pad member (500), even if a thermal event or thermal runaway occurs in the battery cell (110), it is difficult for heat to propagate and venting gas to be discharged in the plane direction, that is, the X-axis or -X-axis direction in which the battery cells (110) are stacked. Accordingly, there is a high possibility that high-temperature venting gas or particles due to thermal runaway of the battery cell (110) will be discharged through the lower end (114a), upper end (114b), or both ends (114c, 114d) of the battery cell (110). There is a high possibility that high-temperature venting gas or particles will be discharged when the sealing is released at the lower end (114a) and both ends (114c, 114d) where the sealing portion (114s) is provided. In particular, the sealing portion (114s) at both ends (114c, 114d) of the battery cell (110) from which the electrode lead (111) protrudes is called a terrace part. In a conventional battery module, venting gas was mainly discharged when the sealing was released at this terrace part.

[0135] However, according to the present embodiment, since the first, third, and fourth frames (310, 330, and 340) of the cell frame (300) are in close contact with the lower end (114a) and both ends (114c, 114d) of the battery cell, respectively, venting gas or particles may be restricted from being discharged through the edges of the battery cell (110). Of course, in the cell frame (300) of another embodiment, the upper end (114b) of the battery cell (110) may also be in close contact with the second frame (320).

[0136] Since a cell vent part (300V) that is open downward is provided in a portion corresponding to the lower end (114a) of the battery cell among the cell frames (300) according to the present embodiment, that is, in the first frame (310), high-temperature venting gas or particles generated during the thermal runaway process of the battery cell (110) can be induced to be discharged only through the cell vent part (300V). That is, in the battery pack (1000) according to the present embodiment, downward directional venting, that is, “lower venting”, can be induced by the cell frame (300) having the cell vent part (300V). In addition, as described above, venting only through the cell vent part (300V) can be more clearly implemented by the adhesive member (130) attached to a portion of the lower end (114a) of the battery cell (110) other than the portion corresponding to the cell vent part (300V).

[0137] Meanwhile, as will be described later, when the battery cell stack (120) is housed in the pack frame, venting gas or particles discharged from the cell vent section (300V) can be discharged to the outside of the pack frame through the inside of the bottom frame of the pack frame. This will be described in detail later with reference to FIGS. 23 to 35.

[0138] In the battery pack (1000), there are high-voltage current paths, such as HV (High voltage) connections of bus bars or terminal bus bars. Here, the HV connection is a connection that serves as a power source to supply power requiring high voltage, and refers to an electrical connection between battery cells. The electrical connection between battery cells can be achieved by connecting the electrode leads (111) of the battery cells (110) to bus bars or terminal bus bars, etc.

[0139] At this time, if high-temperature gas or particles, etc. due to a thermal event of the battery cell (110) come into contact with a high-voltage path such as an HV connection, a short circuit or arc discharge may occur, which may lead to additional explosion and flame generation. In particular, the terrace part is adjacent to the electrode lead (111), bus bar, etc., and the venting gas discharged through the terrace part may be more dangerous because it directly affects the HV connection. On the other hand, in the case of the battery pack according to the present embodiment, as mentioned above, since it has a structure of “bottom venting” through the cell vent part (300V), high-temperature gas or particles due to a thermal event may be discharged downward. In particular, as will be described later, they may be discharged to the outside through the bottom frame of the pack frame. Therefore, there is no risk of high-temperature gas or particles, etc. coming into contact with a high-voltage path such as an HV connection, and ultimately, safety against thermal runaway phenomenon can be improved.

[0140] Meanwhile, as described above, since one side of the cell body (113) of the battery cell (110) is in close contact with the cooling plate (410) or the pad member (500), the cooling plate (410) and the pad member (500) can minimize the heat propagation of the thermal runaway phenomenon occurring in the battery cell (110) to other adjacent battery cells (110). That is, the cooling plate (410) can implement excellent cooling performance capable of controlling heat generation during rapid charging through the surface cooling structure, while simultaneously preventing thermal propagation between the battery cells (110). In particular, the cooling plate (410) has excellent thermal conductivity, so it can lower the thermal runaway temperature of the battery cell (110) and is effective in preventing thermal propagation between the battery cells (110) because it blocks the lateral direction. Likewise, the pad member (500) can also prevent thermal propagation between battery cells (110). If the pad member (500) includes a material with excellent insulating properties, it can be more effective in preventing thermal propagation.

[0141] Meanwhile, during the process of repeated charging and discharging, the battery cells (110) may experience a swelling phenomenon, in which the internal electrolyte decomposes and gas is generated, causing the battery cells (110) to swell. In the swelling phenomenon of the battery cells (110), the battery cells (110) expand in the thickness direction. That is, the battery cells (110) may expand along the direction in which the battery cells (110) are stacked (the direction parallel to the X-axis). The pad member (500) according to the present embodiment can control the swelling while absorbing the swelling of the battery cells (110). Accordingly, the battery cell unit (100) or the battery cell stack (120) can be prevented from being deformed beyond its deformation limit due to the swelling of the battery cells (110).

[0142] Figure 22 is a perspective view of a battery cell unit viewed from below according to one embodiment of the present invention.

[0143] Referring to Fig. 22, the cell vent portion (300V) may have a shape that protrudes downward. In particular, the cell vent portion (300V) may be shaped to protrude in the direction in which the floor frame (1200) described below is located, and be inserted toward the venting space within the floor frame (1200). This will be described again with reference to Fig. 25.

[0144] Fig. 23 is a perspective view showing a pack frame included in a battery pack according to one embodiment of the present invention. Fig. 24 is a perspective view showing a bottom frame and a side frame included in the pack frame of Fig. 23. Fig. 25 is a cross-sectional perspective view taken along the cutting line BB of Fig. 24.

[0145] Referring to FIGS. 1, 4, and 23 to 25 together, a battery pack (1000) according to the present embodiment may include a pack frame (1100) in which battery cells (110) are stored, as described above. Specifically, a battery cell stack (120) may be stored in the pack frame (1100).

[0146] The pack frame (1100) may include a bottom frame (1200) on which battery cells (110) are placed and in which a venting space (VS) is provided. While venting gas is discharged from the battery cells (110), the cell vent part (300V) may be in communication with the venting space (VS) of the bottom frame (1200). Specifically, while venting gas is discharged from the battery cells (110) due to thermal runaway in the battery cells (110), the cell vent part (300V) may be in communication with the venting space (VS) of the bottom frame (1200). Accordingly, the venting gas may move from the cell vent part (300V) to the venting space (VS) of the bottom frame (1200).

[0147] In particular, the cell vent part (300V) may be formed to protrude in the direction in which the floor frame (1200) is located and be inserted toward the venting space (VS) inside the floor frame (1200). A floor frame hole (1200H) may be formed in the floor frame (1200), and when the cell vent part (300V) is fitted into the floor frame hole (1200H), the cell vent part (300V) may be connected to the venting space (VS). Accordingly, the form in which the cell vent part (300V) and the venting space (VS) are connected can be more clearly implemented, and the leakage of venting gas and particles between the cell vent part (300V) and the floor frame (1200) into a gap other than the venting space (VS) can be minimized.

[0148] High-temperature venting gas and particles introduced into the venting space (VS) can be discharged to the outside of the battery pack (1000). The battery pack (1000) according to the present embodiment has a so-called “bottom venting” structure that discharges high-temperature venting gas and particles to the outside using the bottom frame (1200). If high-temperature venting gas or particles caused by a thermal event of the battery cell (110) come into contact with a high-voltage path such as an HV connection, a short circuit or an arc discharge may occur, which may lead to additional explosion and flame generation. On the other hand, in the case of the battery pack (1000) according to the present embodiment, as mentioned above, since it has a “bottom venting” structure, high-temperature venting gas or particles caused by a thermal event are discharged downward, i.e., through the bottom frame (1200). Therefore, there is no risk of high-temperature venting gases or particles reaching high-voltage paths such as HV connections, and ultimately, safety against thermal runaway can be improved.

[0149] Fig. 26 is a perspective view showing a BMS frame included in the pack frame of Fig. 23.

[0150] Referring to FIGS. 1, 23, 24, and 26, the pack frame (1100) according to the present embodiment may include a bottom frame (1200) on which a battery cell stack (120) is placed, and a side frame (1300) extending upward from one end of the bottom frame (1200). Meanwhile, the pack frame (1100) according to the present embodiment may include a BMS frame (1900) on which a BMS (Battery Management System) module (not shown) is mounted. The side frame (1300) may be positioned on one side of the battery cell stack (120), and the BMS frame (1900) on which a BMS module (not shown) is mounted may be positioned on the other side opposite to the one side of the battery cell stack (120). That is, the side frame (1300) and the BMS frame (1900) may be positioned on opposite sides of the battery cell stack (120).

[0151] The BMS frame (1900) may include a first side cover portion (1910), a second side cover portion (1920), and a lower cover portion (1930). A BMS module (not shown) may be placed on the lower cover portion (1930), and the first side cover portion (1910) and the second side cover portion (1920) may extend upward from opposite ends of the lower cover portion (1930).

[0152] The BMS module can collect voltage data and temperature data for battery cells (110) inside the battery pack (1000). The BMS module can control the operation of the battery pack (1000) based on the collected voltage data and temperature data.

[0153] As described above, in the battery pack (1000) according to the present embodiment, the battery cells (110) are directly mounted on the pack frame (1100) with the edges of the battery cells (110) covered by the cell frame (300). Specifically, rather than the battery cells (110) being housed in a separate module frame, the battery cell unit (100) including the battery cells (110) can be placed on the bottom frame (1200) of the pack frame (1100) and directly mounted on the pack frame (1100). Since the conventional module frame is removed and the battery cells (110) are directly mounted on the pack frame (1100), in the case of the battery pack (1000) according to the present embodiment, the packing structure can be minimized, and thus the space utilization and energy density of the battery pack (1000) can be improved. That is, the battery pack (1000) according to the present embodiment may have a so-called CTP (Cell to Pack) structure in which the battery cells (110) are mounted directly on the pack frame (1100).

[0154] Instead of removing the conventional module frame, in order to fix the battery cell stack (120) within the pack frame (1100), the side frame (1300) and the BMS frame (1900) can press the one side and the other side of the battery cell stack (120), respectively. The first side cover part (1910) of the BMS frame (1900) can press the other side of the battery cell stack (120). Since the battery cells (110) are directly mounted on the pack frame (1100), unnecessary structures are eliminated, which is advantageous in terms of space utilization and energy density, but the trade-off is that the battery cell stack (120) within the pack frame (1100) may be vulnerable to vibration or external impact. Therefore, fixing the battery cell stack (120) in the battery pack (1000) of the CTP (Cell to Pack) structure may be an important issue. Accordingly, in the present embodiment, the side frames (1300) and the BMS frame (1900) located on opposite sides can be configured to press the battery cell stack (120) in a direction toward each other. Accordingly, the structural stability of the battery pack (1000) having a CTP (Cell to Pack) structure can be supplemented.

[0155] Below, a method for manufacturing a battery pack (1000) using a pressurizing method of a side frame (1300) and a BMS frame (1900) will be described.

[0156] Figures 27 and 28 are drawings for explaining a method of arranging battery cell units in a pack frame.

[0157] Referring to FIGS. 1, 4, and 23 to 28 together, a battery cell unit (100) including a plurality of battery cells (110) covered by a cell frame (300) can be placed on a bottom frame (1200) of a pack frame (1100). At this time, the first battery cell unit (100) can be placed right next to a side frame (1300), and subsequent battery cell units (100) can be placed while sequentially applying pressure in a direction away from the side frame (1300).

[0158] At this time, the cell vent part (300V) of the cell frame (300) can be fitted into the bottom frame hole (1200H) while having a protruding shape. That is, in the process of sequentially stacking the battery cell units (100), when the cell vent part (300V) is fitted into the bottom frame hole (1200H), each battery cell unit (100) can be properly installed in the correct position. That is, the cell vent part (300V) having a protruding shape can not only minimize the leakage of venting gas and particles from the battery cell (110) into gaps other than the venting space (VS), but also serve the function of aligning the battery cell units (100) during the process of manufacturing the battery pack (1000).

[0159] As the last battery cell unit (100) is placed on the bottom frame (1200), the battery cell stack (120) is finally formed, and as the BMS frame (1900) presses the other side of the formed battery cell stack (120), the battery cell stack (120) can be fixed.

[0160] In this manner, during the process of manufacturing the battery pack (1000), the side frame (1300) and the BMS frame (1900) can press the battery cell stack (120) toward each other. Accordingly, the structural stability of the battery pack (1000) having a CTP (Cell to Pack) structure can be improved.

[0161] Meanwhile, a process of connecting the electrode leads (111) of the battery cells (110) to each other via a bus bar or the like and a process of applying a thermal resin layer to the upper portion of the battery cells (110) may follow.

[0162]

[0163] Below, the structure of a pack frame according to another embodiment of the present invention will be described.

[0164] Fig. 29 is a perspective view showing a pack frame according to another embodiment of the present invention. Fig. 30 is a perspective view showing a floor frame included in the pack frame of Fig. 29.

[0165] Referring to FIGS. 29 and 30, the pack frame (1100) according to the present embodiment may include a bottom frame (1200) provided with a venting space (VS) as described above. In addition, the pack frame (1100) may include a side frame (1300) extending along an edge of the bottom frame (1200). For example, the side frame (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) may be arranged along four sides of an edge of the bottom frame (1200) having a rectangular shape. A storage space with an open upper portion is provided by the bottom frame (1200) and the side frames (1300), and battery cells (110) can be arranged in this storage space. After the battery cells (110) are arranged in the storage space, a pack cover, which will be described later, can cover the open upper portion of the storage space. The pack cover can be joined to the side frame (1300) of the pack frame (1100), and for example, welding or adhesive joining can be applied. The battery cells (110) can be sealed by the pack frame (1100) and the pack cover. In addition, a gasket can be interposed between the pack cover and the side frame (1300) to enhance sealing properties.

[0166] Meanwhile, the battery pack (1000) according to the present embodiment may include a mounting beam (1300M) provided on a side frame (1300) for fixing the battery pack (1000). For example, the mounting beams (1300M) formed on the side frame (1300) are illustrated in FIG. 29. The mounting beams (1300M) may be utilized when mounting the battery pack (1000) on a device. For example, when mounting the battery pack (1000) on a vehicle device, the mounting beams (1300M) may be fixed to the chassis of the vehicle.

[0167] Additionally, according to the present embodiment, the battery pack (1000) may include a vertical beam (1800) positioned on the floor frame (1200) and dividing a space in which battery cells (110) are positioned. As an example, FIG. 29 shows three vertical beams (1800) dividing the storage space into three zones.

[0168] A venting space (VS) is provided in the bottom frame (1200) through which venting gas and particles, etc., discharged from the cell vent part (300V) move. The cell vent part (300V) of the cell frame (300) can be connected to the venting space (VS) of the bottom frame (1200). Specifically, while the venting gas is discharged from the battery cell (110) due to thermal runaway in the battery cell (110), the cell vent part (300V) is connected to the venting space (VS) of the bottom frame (1200). Accordingly, the venting gas can move from the cell vent part (300V) to the venting space (VS) of the bottom frame (1200).

[0169] In particular, the cell vent part (300V) may be formed to protrude in the direction in which the floor frame (1200) is located and be inserted toward the venting space (VS) inside the floor frame (1200). Accordingly, the form in which the cell vent part (300V) and the venting space (VS) are connected can be more clearly implemented, and the leakage of venting gas and particles between the cell vent part (300V) and the floor frame (1200) into a gap other than the venting space (VS) can be minimized.

[0170] High-temperature venting gas and particles introduced into the venting space (VS) can be discharged to the outside of the battery pack (1000). The battery pack (1000) according to the present embodiment has a so-called “lower venting” structure that discharges high-temperature venting gas and particles to the outside using the bottom frame (1200). A detailed description of the lower venting is omitted as it overlaps with the previously described content.

[0171] Fig. 31 is a perspective view showing the inner frame and cover plates included in the bottom frame of Fig. 30. Fig. 32 is a partial drawing showing an enlarged portion of the “C” portion of Fig. 31.

[0172] Referring to FIGS. 29 to 32 together, a bottom frame (1200) according to one embodiment of the present invention may include an outer frame (1210) and an inner frame (1220) positioned above the outer frame (1210). The outer frame (1210) may be a plate positioned at the lowest end of the battery pack (1000), and the outer frame (1210) may be coupled to a side frame (1300).

[0173] The inner frame (1220) is a plate-shaped member, but may include concave portions (1221) and convex portions (1222). In the inner frame (1220), the concave portions (1221) and convex portions (1222) may be alternately arranged along the Y-axis direction. Meanwhile, in order to form a venting space (VS), a cover plate (1500) or the like may be coupled to both side surfaces of the inner frame (1220). The inner frame (1220) and the cover plate (1500) may be coupled by a method such as welding.

[0174] The venting space (VS) according to the present embodiment may include a first venting space (VS1) and a second venting space (VS2). Specifically, a portion of the concave portion (1221) of the inner frame (1220) surrounded by the cover plate (1500) and the battery cell stack (120) may correspond to the first venting space (VS1). The venting gas discharged from the cell vent portion (300V) may move to the first venting space (VS1).

[0175] In addition, a portion of the convex portion (1222) of the inner frame (1220) surrounded by the cover plate (1500) may correspond to a second venting space (VS2). In addition, the inner frame (1220) may include a plurality of filtering holes (1220H) that connect the first venting space (VS1) and the second venting space (VS2). That is, the venting gas (VG) introduced into the first venting space (VS1) may move to the second venting space (VS2) through the filtering holes (1220H). Particles, ash, byproducts, etc. contained in the high-temperature venting gas (VG) may be primarily filtered out while passing through these filtering holes (1220H). That is, in the case of the floor frame (1200) according to the present embodiment, the venting space (VS) is divided into a first venting space (VS1) and a second venting space (VS2), and the first venting space (VS1) and the second venting space (VS2) are connected through a filtering hole (1220H), thereby exerting a function of primarily filtering high-temperature venting gas (VG).

[0176] Meanwhile, a gas shield (1600) may be placed in the concave portion (1221) of the inner frame (1220). Specifically, the gas shield (1600) may be placed in the concave portion (1221) to separate the first venting space (VS1) located below one battery cell unit (100) from the first venting space (VS1) located below another battery cell unit (100).

[0177] Fig. 33 is a perspective view of the bottom frame of Fig. 30 with a portion of the inner frame removed. Fig. 34 is a perspective view of the bottom frame of Fig. 30, showing the outer frame and routing plates. Fig. 35 (a) is a partial view showing an outer frame hole, and Fig. 35 (b) is a partial view showing a venting device coupled to the outer frame hole.

[0178] Referring to FIGS. 31 to 35 together, a routing plate (1700) may be positioned inside the convex portion (1222) of the inner frame (1220), i.e., in the second venting space (VS2). The routing plate (1700) may be a structure that has an internal space and extends along one direction (a direction parallel to the X-axis).

[0179] The battery pack (1000) may include a venting device (VD) provided in the pack frame (1100). For example, an outer frame hole (1210H) may be formed in the outer frame (1210), and a venting device (VD) may be mounted in the outer frame hole (1210H). The venting device (VD) is a general term for a member or mechanism provided to discharge venting gas, etc. For example, the venting device (VD) may be a valve structure that opens or bursts when the internal pressure exceeds a certain level.

[0180] At this time, the outer frame hole (1210H) and the venting device (VD) may be located in the inner space of the routing plate (1700). Accordingly, the venting gas (VG) introduced into the second venting space (VS2) through the filtering hole (1220H) as shown in FIG. 32 may be bent multiple times while moving into the inner space of the routing plate (1700) as shown in FIG. 33.

[0181] In this way, as the routing plate (1700) is provided inside the second venting space (VS2), the venting gas (VG) or particles introduced into the second venting space (VS2) move along the elongated venting path and bend the path several times. While the venting gas (VG) flows along the path elongated by the routing plate (1700), the temperature of the venting gas (VG) or particles may be lowered. Therefore, the venting gas (VG) or particles may be prevented from triggering an explosion. In addition, as the path of the venting gas (VG) is elongated, oxygen introduced from the outside of the battery pack (1000) is blocked from encountering the venting gas, etc., thereby preventing an explosion from occurring. In addition, large particles may be filtered out in the elongated path.

[0182]

[0183] Figure 36 is a partial cross-sectional view of a battery pack according to one embodiment of the present invention.

[0184] Referring to FIGS. 16, 17, and 36 together, a thermal resin layer (800) formed by applying thermal resin to the upper portion of the battery cells (110) as described above may be positioned. A pack cover (1400) covering the upper portion of the pack frame (1100) and having a coolant flowing therein may be positioned on the upper portion of the thermal resin layer (800). That is, a cooling channel (1400C) through which a coolant flows may be formed inside the pack cover (1400) covering the upper portion of the pack frame (1100). At this time, the thermal resin layer (800) may be in direct contact with the pack cover (1400).

[0185] The cooling plate (410) cools the battery cell (110) in a plate-like shape, and the heat generated from the battery cell (110) can be transferred to the pack cover (1400) having a cooling path (1400C) formed therein, sequentially passing through the cooling plate (410) and the thermal resin layer (800). That is, the heat generated from the battery cell (110) can be ultimately cooled by the pack cover (1400). In the case of the battery pack (1000) according to the present embodiment, the heat generated from the battery cell (110) can be structured such that it is ultimately discharged and cooled through the upper portion of the battery pack (1000).

[0186] In this example, terms indicating directions such as front, back, left, right, up, and down are used, but these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0187] The battery pack according to the embodiment described above may include various control and protection systems, such as a BDU (Battery Disconnect Unit) and a cooling system, in addition to a BMS (Battery Management System).

[0188] The above battery pack can be applied to various devices. Specifically, it can be applied to transportation vehicles such as electric bicycles, electric vehicles, and hybrid vehicles, as well as ESS (Energy Storage Systems), but is not limited thereto. It can also be applied to various devices that can use secondary batteries.

[0189] Although the 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 made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

[0190] Description of the symbol

[0191] 100: Battery cell unit

[0192] 110: Battery cell

[0193] 120: Battery cell stack

[0194] 300: Cell Frame

[0195] 300V: Cell vent

[0196] 400: Heat sink

[0197] 410: Cooling plate

[0198] 500: Absence of pad

[0199] 1000: Battery pack

[0200] 1100: Pack Frame

[0201] 1200: Floor frame

[0202] 1300: Side frame

[0203] 1400: Pack Cover

Claims

1. A plurality of battery cells stacked along one direction; Cell frames extending along the edges of the battery cells and covering the edges of the battery cells; and including a pack frame in which the above battery cells are stored; A battery pack in which the battery cells are directly mounted on the pack frame, with the edges of the battery cells covered by the cell frame.

2. In paragraph 1, One of the above cell frames covers the edges of a plurality of the above battery cells, A plurality of battery cells covered by one of the above cell frames are positioned along the length direction, A battery pack in which the above longitudinal direction is parallel to the direction in which the electrode leads protrude from the battery cell.

3. In paragraph 2, A battery pack comprising: a first frame covering the lower portions of the battery cells; a third frame covering one end of one of the battery cells; and a fourth frame covering one end of another of the battery cells.

4. In paragraph 3, The portion corresponding to the upper portion of the battery cell among the above cell frames is opened, A thermal resin layer is formed by applying thermal resin on top of the above battery cells, A battery pack in which the upper part of the above battery cell is in contact with the above thermal resin layer.

5. In paragraph 1, A battery pack including a first frame covering the lower portion of the battery cell, and a third frame and a fourth frame covering both ends of the battery cell, respectively.

6. In paragraph 5, The above cell frame is a battery pack including a second frame covering the upper portion of the battery cell.

7. In paragraph 1, A battery pack in which a cell vent portion is formed in a portion corresponding to the lower portion of the battery cell among the cell frames.

8. In paragraph 7, The above pack frame includes a bottom frame on which the battery cells are placed and a venting space is provided, A battery pack in which the cell vent portion communicates with the venting space of the bottom frame while venting gas is discharged from the battery cell.

9. In paragraph 7, A battery pack in which an adhesive material is attached to a portion of the lower portion of the battery cell except for a portion corresponding to the cell vent.

10. In paragraph 7, The above battery cell includes an electrode assembly and a pouch case for storing the electrode assembly, A battery pack in which the lower part of the above battery cell is a sealing part formed by sealing the end of the pouch case.

11. In paragraph 1, A battery pack in which the battery cells located inside are fixed by joining adjacent cell frames together.

12. In paragraph 1, A battery pack in which at least one cooling plate is positioned at at least one location between the above battery cells.

13. In paragraph 12, A thermal resin layer is formed by applying thermal resin on top of the above battery cells, A battery pack in which the upper part of the cooling plate is in contact with the thermal resin layer.

14. In paragraph 1, The above battery cells are stacked along the above direction to form a battery cell stack, The above pack frame includes a bottom frame on which the battery cell stack is placed and a side frame extending upward from one end of the bottom frame, A battery pack in which the side frame is positioned on one side of the battery cell stack, and a BMS frame on which a BMS (Battery Management System) module is mounted is positioned on the other side opposite to the one side of the battery cell stack.

15. In paragraph 14, A battery pack in which the side frame and the BMS frame pressurize one side and the other side of the battery cell stack, respectively.

16. A device including a battery pack according to paragraph 1.

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