Cell assemblies and battery packs containing them

Abstract

The present invention relates to a cell assembly including a cell stack in which a plurality of cells having protruding electrode leads are stacked, and heat transfer prevention pads having heat transfer resistance and provided on both sides of the cell stack, and a battery pack including the cell assembly.

Description

【Technical Field】 【0001】 The present invention relates to a cell assembly and a battery pack including the same, and more specifically, to a cell assembly having thermal safety and a battery pack including the same. 【0002】 This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0120778 filed on September 12, 2023 and Korean Patent Application No. 10-2024-0014106 filed on January 30, 2024, and all the contents disclosed in the documents of these Korean patent applications are incorporated herein by reference. 【Background Art】 【0003】 The operating voltage of one cell included in a secondary battery is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a plurality of cells may be connected in series to form a battery pack. Also, depending on the charge / discharge capacity required for the battery pack, a large number of cells may be connected in parallel to form a battery pack. Therefore, the number of cells included in the above battery pack can be variously set according to the required output voltage or charge / discharge capacity. 【0004】 When configuring a battery pack by connecting a plurality of cells in series / parallel, it is common to first configure a cell assembly including at least two or more cells, and then add such a cell assembly and other components to configure a battery pack. 【0005】 The above battery pack has a box-shaped metal material housing structure, and a plurality of cell assemblies are housed inside so as to be in close contact. That is, each cell assembly is arranged in the battery pack in a state of being maximally adhered so that there is no wasted space. 【0006】 However, the above structure has a problem: it is extremely vulnerable if any one of the cell assemblies catches fire. In other words, if one cell assembly experiences thermal runaway and generates high temperatures, this heat can be instantly transferred to other adjacent cell assemblies, potentially leading to a dangerous situation where the entire cell assembly housed inside the battery pack explodes. 【0007】 When the above battery pack is applied to electric vehicles, etc., it is necessary to delay the heat transfer as much as possible from the moment an abnormal phenomenon occurs until an explosion occurs, thereby gaining time for the driver to evacuate. 【0008】 Therefore, conventional research has focused on methods to minimize the time it takes for heat to transfer from one cell assembly experiencing thermal runaway to other cell assemblies. [Prior art documents] [Patent Documents] 【0009】 [Patent Document 1] Korean Patent Publication No. 10-2021-0041950 [Overview of the project] [Problems that the invention aims to solve] 【0010】 Therefore, the present invention was devised to solve the above-mentioned problems, and aims to provide a cell assembly with a structure that can suppress the dissipation of heat to the greatest extent possible when high temperatures are generated in multiple stacked cells due to abnormal phenomena. 【0011】 Furthermore, the present invention aims to provide a battery pack with a structure that can delay heat transfer between multiple cell assemblies housed within it. 【0012】 Other objects and advantages of the present invention can be understood from the following description and will be more clearly seen from the embodiments of the present invention. Furthermore, it will be readily apparent that the objects and advantages of the present invention can be realized by the means and combinations thereof as set forth in the claims. [Means for solving the problem] 【0013】 The present invention provides a cell assembly comprising: a cell stack in which a plurality of cells with protruding electrode leads are stacked; a busbar frame that includes busbars electrically connected to the electrode leads of each cell and is coupled to at least one of the front and rear surfaces of the cell stack; and thermal transfer prevention pads that have thermal transfer resistance and are provided on both sides of the cell stack. 【0014】 The above-mentioned heat transition prevention pad may include a heat-absorbing pad containing a phase change material that absorbs external heat, and a heat-insulating pad with high thermal resistance. 【0015】 The above-mentioned heat transfer prevention pad is provided such that either the heat absorption pad or the heat insulation pad is attached to one surface of the cell that is stacked on the outermost layer of the cell stack. 【0016】 The system further includes a pair of support members provided on both sides of the cell stack and coupled to the sides of the busbar frame to support the plurality of cells, wherein the thermal transfer prevention pad can be interposed between the cell stack and the support members. 【0017】 The cell stack described above may further include compression pads interposed between any pair of cells from the plurality of cells described above. 【0018】 Further, according to the present invention, there is provided a battery pack including the cell assembly of the present invention and a pack case including a seating space in which the cell assembly is seated, wherein the pack case includes a base plate that supports a lower portion of the cell assembly and a side beam that is coupled to an edge of the base plate so as to support a side portion of the cell assembly. 【0019】 A plurality of cell assemblies are seated in the seating space, and the pack case may further include a cross beam provided between any adjacent pair of cell assemblies. 【0020】 The cross beam can be closely adhered and coupled to a side portion of the cell assembly so that there is no gap between the cross beam and the cell assembly. 【0021】 A side surface of the cross beam can be in close contact with a heat absorption pad of the cell assembly facing the cross beam. 【0022】 The cross beam is coupled to each adjacent cell assembly, and the cross beam can be coupled to the base plate so as to fix the cell assembly to the pack case. 【0023】 The heat transfer prevention pad may include a phase change material and may include a heat absorption pad that absorbs external heat and a heat insulation pad having high heat resistance. 【0024】 The cell assembly is provided on both sides of the cell stack and further includes a pair of support members coupled to side portions of the bus bar frame so as to support the plurality of cells, and any adjacent pair of cell assemblies can be fixed to each other by coupling respective support members facing each other. 【0025】 The heat transfer prevention pad can be interposed between the cell stack and the support member. 【0026】 The above support member can be closely adhered and coupled to the heat transfer prevention pad so that there is no gap between the support member and the heat transfer prevention pad. 【Advantages of the Invention】 【0027】 The cell assembly of the present invention and the battery pack of the present invention including the cell assembly have the effect of improving thermal safety. 【Brief Description of the Drawings】 【0028】 [Figure 1] It is an exploded perspective view of a cell assembly according to a first embodiment of the present invention. [Figure 2] It is a perspective view showing a state in which an end plate is coupled to the cell assembly of FIG. 1 above. [Figure 3] It shows a cross section obtained by cutting the cell assembly of FIG. 1 above in the width direction of the cell assembly. [Figure 4] It is a perspective view of a cell assembly according to a second embodiment of the present invention. [Figure 5] It is an exploded perspective view showing a state in which a plurality of cell assemblies according to the first embodiment are aligned. [Figure 6] It is a perspective view showing a main part of a pack case to which a plurality of aligned cell assemblies are mounted. [Figure 7] It is a cross-sectional view of a pair of cell assemblies with any one cross beam interposed therebetween in the battery pack of FIG. 6 above. [Figure 8] It is a perspective view showing a pack case to which a plurality of cell assemblies according to the second embodiment are mounted. [Figure 9] It is a cross-sectional view showing a cross section of a pair of cell assemblies that are in close contact with each other in the battery pack of FIG. 8 above. 【Modes for Carrying Out the Invention】 【0029】 Preferred embodiments of the present invention will now be described in detail with reference to the attached drawings. Thereafter, terms and words used in this specification and in the claims shall not be interpreted in their ordinary or dictionary sense, but rather in a sense and concept consistent with the technical idea of ​​the present invention, based on the principle that inventors may appropriately define the concepts of terms in order to best describe their invention. 【0030】 Therefore, the embodiments described herein and the configurations shown in the drawings represent only the most preferred embodiments of the present invention and do not represent the entire technical concept of the present invention; there may be a variety of equivalents and modifications that can substitute for them at the time of filing. 【0031】 Furthermore, in describing the present invention, if it is determined that a specific description of a related known configuration or function may obscure the gist of the present invention, such detailed description will be omitted. 【0032】 Embodiments of the present invention are provided to those skilled in the art to better illustrate the invention; therefore, the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown schematically for the sake of clarity. Accordingly, the sizes and proportions of each component do not fully reflect their actual sizes and proportions. 【0033】 The present invention relates to a cell assembly and a battery pack containing the same, characterized in that the battery pack of the present invention improves thermal safety by suppressing heat transfer between each of the contained cell assemblies to the greatest extent possible. 【0034】 Figures 1 to 3 relate to a cell assembly according to the first embodiment of the present invention, Figure 4 relates to a cell assembly according to the second embodiment of the present invention, Figures 5 to 7 relate to a battery pack including the cell assembly according to the first embodiment of the present invention, and Figures 8 and 9 relate to a battery pack including the cell assembly according to the second embodiment of the present invention. 【0035】 Specific embodiments of the cell assembly and battery pack of the present invention will be described in detail below with reference to the attached drawings. For reference, the front-to-back and up-down-left-right directions used in the following description to specify relative positions are for the purpose of understanding the invention and refer to the directions shown in the drawings unless otherwise specified. 【0036】 Here, the width direction of the cell assembly is defined as the direction in which the cells are stacked, and the longitudinal direction of the cell assembly is defined as the direction perpendicular to the width direction of the cell assembly, that is, the direction connecting both sides to which the busbar frame or end plate is joined. 【0037】 Furthermore, the width direction of the battery pack refers to the longitudinal direction of the cell assembly housed in the battery pack, and the longitudinal direction of the battery pack refers to the width direction of the cell assembly housed in the battery pack. 【0038】 Cell assembly 100 The cell assembly 100 of the present invention includes a cell stack 110 containing a plurality of cells 111. 【0039】 The cell 111 described above consists of an electrode assembly in which electrodes including a negative electrode and a positive electrode and a separator membrane are alternately stacked, electrode leads electrically connected to the electrodes, and a battery case that surrounds and seals the electrode assembly so that the electrode leads protrude to the outside. 【0040】 The above-mentioned cell 111 can be classified into a rectangular cell 111 and a pouch-type cell 111 depending on the form of the electrode assembly and the battery case. 【0041】 The above-mentioned rectangular cell 111 can be in a stack configuration in which the assembly is stacked with electrodes and separation membranes alternately layered, or it can be in a stack-fold configuration in which electrodes and the like are provided on a sheet-like separation membrane that is folded at regular intervals. 【0042】 The above-mentioned rectangular cell 111 has its electrode assembly inserted into a square, box-shaped battery case. 【0043】 The above-mentioned pouch-type cell 111 may have an electrode assembly in a stacked configuration or in a stack-fold configuration. 【0044】 In the pouch-type cell 111 described above, the electrode assembly is inserted into a pouch-shaped battery case. Therefore, the cell assembly 100 may include any one of the following cells 111: a cylindrical cell 111, a rectangular cell 111, and a pouch-type cell 111. 【0045】 The cell assembly 100 includes a busbar frame 120 which includes a plurality of cells 111 and busbars 121 that are electrically connected to the electrode leads contained in each of the cells 111. 【0046】 The cell assembly 100 may further include a modular frame surrounding the cell stack 110 so that each cell 111 can be protected from external impacts. In this case, the modular frame may be provided to support or protect only a portion of the cell stack 110, or it may be provided over all exposed portions of the cell stack 110 to completely isolate the cell stack 110 from the outside. 【0047】 However, in the embodiments of the present invention, in order to make the internal structure easier to understand, the description will focus on a cell assembly 100 to which the above-described module frame configuration does not apply. 【0048】 (First Embodiment) Figure 1 is an exploded perspective view of a cell assembly 100 according to a first embodiment of the present invention. 【0049】 The cell assembly 100 of the present invention includes a cell stack 110 and a busbar frame 120, as shown in Figure 1 above. 【0050】 The cell stack 110 described above is a configuration in which multiple cells 111 are stacked in one direction. 【0051】 Each of the above cells 111 includes an electrode assembly in which electrodes and a separation membrane are alternately stacked, an electrode lead connected to the electrode, a case surrounding the electrode assembly such that the electrode lead protrudes to the outside, and an electrolyte filled together with the electrode assembly inside the case. 【0052】 The above electrode may be a positive electrode in which a slurry of positive electrode active material, binder resin, conductive material and other additives is applied to at least one surface of the current collector, or a negative electrode in which a slurry of negative electrode active material, binder resin, conductive material and other additives is applied to at least one surface of the current collector. Therefore, the above electrode assembly is constructed by alternately stacking positive electrodes, separator films and negative electrodes. 【0053】 The positive electrode active material may include a lithium-containing transition metal oxide, and the negative electrode active material may include lithium metal, carbon material, and metal compounds or mixtures thereof, in which lithium ions can be intercalated and released. 【0054】 The above-mentioned separation membrane can be made from a conventional porous polymer film used in lithium-ion batteries. 【0055】 In the above case, the sheet material is processed into a predetermined shape. In this case, the sheet material is composed of a multilayer structure in which an outermost resin layer made of an insulating material such as polyethylene terephthalate (PET) or nylon (registered trademark), a metal layer made of aluminum that maintains mechanical strength and prevents the penetration of moisture and oxygen, and an inner resin layer made of a polyolefin-based material that has heat adhesion and acts as a sealant are laminated together. 【0056】 In the sheet material forming the above case, a predetermined adhesive resin layer may be interposed between the internal resin layer and the metal layer, and between the external resin layer and the metal layer, as needed. The adhesive resin layer is for smooth adhesion between dissimilar materials and is formed in single or multilayer form. The material used is usually a polyolefin resin, or a polyurethane resin for smooth processing, and mixtures thereof can also be used. 【0057】 The cell 111 described above can be classified into rectangular, pouch-type, and cylindrical types depending on the form of the electrode assembly and case. However, in the detailed description and drawings of the present invention, the pouch-type cell 111 will be used as an example for ease of understanding. 【0058】 The busbar frame 120 includes busbars 121 that are electrically connected to the electrode leads of the cell stack 110 and are coupled to at least one of the front and rear surfaces of the cell stack 110. 【0059】 The busbar frame 120 not only pressurizes and aligns each cell 111 contained in the cell stack 110, but also serves to bundle the electrode leads protruding from each cell 111. Specifically, a conductive busbar 121 is fixedly provided on the busbar frame 120, and the multiple electrode leads drawn out from the cell stack 110 are coupled to the busbar frame 120. At this time, the coupling between the electrode leads and the busbar frame 120 can usually be carried out by welding, but any other coupling method that can electrically connect the electrode leads and the busbar frame 120 can be used. 【0060】 The cell assembly 100 may further include an end plate 130 that covers the busbar frame 120. 【0061】 Figure 2 is a perspective view showing the cell assembly 100 of Figure 1 with the end plate 130 attached. 【0062】 The cell assembly 100 may further include an end plate 130 provided to cover the busbar frame 120 in order to protect the busbar frame 120 from external impacts, as shown in Figures 1 and 2. 【0063】 The cell assembly 100 of the present invention may further include heat transfer prevention pads 140 having heat transfer resistance on both sides of the cell stack 110. 【0064】 Figure 3 shows a cross-section of the cell assembly 100 in Figure 1, obtained by cutting it in the width direction of the cell assembly 100. 【0065】 As shown in Figure 3, a pair of heat transfer prevention pads 140 are provided on both sides of the cell stack 110. 【0066】 The above-mentioned heat transfer prevention pad 140 includes a heat absorption pad 141 and a heat insulation pad 142. That is, the above-mentioned heat transfer prevention pad 140 includes a heat absorption pad 141 and a heat insulation pad 142 that are joined together. 【0067】 Specifically, the heat-absorbing pad 141 contains a phase-change material and plays a role in absorbing heat from the material it comes into contact with. 【0068】 The heat-absorbing pad 141 contains a heat-absorbing material that is either solid or liquid, and the heat-absorbing material absorbs heat from the material in contact with the heat-absorbing pad 141 and undergoes a phase change. Therefore, the heat-absorbing pad 141 can absorb a certain portion of the heat from the material in contact with it. 【0069】 The above-mentioned heat-insulating pad 142 is characterized by its high thermal resistance. 【0070】 Specifically, the insulation pad 142 contains an insulating material with low thermal conductivity, and this insulating material prevents heat transfer through the insulation pad 142. 【0071】 In some embodiments, as shown in Figure 3, the heat-absorbing pad 141 is provided facing one side of the cell 111 which is stacked on the outermost edge of the cell stack 110, and the heat-insulating pad 142 is interposed between the heat-absorbing pad 141 and the cell stack 110. 【0072】 In another embodiment, although not shown, the heat insulating pad 142 is provided facing one side of the cell 111 which is stacked on the outermost edge of the cell stack 110, and the heat absorbing pad 141 is interposed between the heat insulating pad 142 and the cell stack 110. 【0073】 In other words, the heat transfer prevention pad 140 is provided such that one of the heat insulation pad 142 and the heat absorption pad 141 is attached to one surface of the cell stack 110. 【0074】 The heat-absorbing pad 141 temporarily prevents heat transfer via the heat-insulating pad 142 that is in contact with the cell stack 110 when high-temperature heat is generated in the adjacent cell stack 110. In addition, some of the heat conducted through the heat-insulating pad 142 is secondarily absorbed by the heat-absorbing pad 141. 【0075】 The heat-absorbing pad 141 described above is characterized by its ability to absorb external heat. 【0076】 The heat transfer prevention pad 140 of the present invention, which includes the heat absorption pad 141 and the heat insulation pad 142, absorbs the heat when the substance in contact with it dissipates heat, and at the same time minimizes the passage of heat. 【0077】 In some embodiments, the cell stack 110 may further include a compression pad 160 interposed between any pair of cells 111 among the plurality of cells 111. 【0078】 The cell stack 110 described above may include a plurality of compression pads 160 interposed between the cells 111. In this case, the spacing between the compression pads 160 may be regular or irregular, as shown in Figure 3. For example, one cell 111 may be located between a pair of compression pads 160, or a number of cells 111 may be located between them. 【0079】 The compression pad 160 described above can at least partially absorb the shocks and pressures that may occur between the stacked cells 111. 【0080】 The compression pads 160 are inserted into the cell stack 110 at regular intervals to physically separate the cells 111. 【0081】 (Second Embodiment) Figure 4 is a perspective view of a cell assembly 100 according to a second embodiment of the present invention. 【0082】 Referring to Figure 4, the cell assembly 100 may further include support members 150 for protecting both sides of the exposed cell stack 110. 【0083】 In other words, the cell assembly 100 of the present invention may further include a pair of support members 150 provided on both sides of the cell stack 110 to support the plurality of cells 111, as shown in Figure 4 above. 【0084】 The support member 150 serves to protect the cell stack 110 and the heat transfer prevention pads 140 provided on both sides of the cell stack 110 from external impacts. 【0085】 Furthermore, the support member 150 plays a role in providing a place to directly connect connecting members such as bolts and screws in order to fix the cell stack 110 to the battery pack when attaching the cell assembly 100 to the battery pack. 【0086】 Furthermore, the support member 150 can also serve to prevent heat transfer between the cell assembly 100 including the support member 150 and other cell assemblies 100 adjacent to it. 【0087】 In some embodiments, the support member 150 can be coupled to the side of a busbar frame 120 provided adjacent to the cell stack 110. 【0088】 In some embodiments, the support member 150 can be coupled to the side of an end plate 130 provided on the busbar frame 120. 【0089】 Battery pack The battery pack of the present invention includes a cell assembly 100 and a pack case 200 in which the cell assembly 100 is mounted. That is, multiple cell assemblies 100 according to the first or second embodiment can be assembled and mounted in a single pack case 200 to form a battery pack. 【0090】 Figure 5 is an exploded perspective view showing a plurality of cell assemblies 100 according to the first embodiment in an aligned state, and Figure 6 is a perspective view showing the main part of the pack case 200 in which the aligned plurality of cell assemblies 100 are mounted. 【0091】 Referring to Figures 5 and 6, the battery pack of the present invention includes a cell assembly 100 of the present invention and a pack case 200 that includes a mounting space A in which the cell assembly 100 is mounted. 【0092】 In some embodiments, the pack case 200 includes a base plate 210 provided to cover and support the lower part of a plurality of cell assemblies 100, and side beams 220 provided to cover and support the sides. 【0093】 In some embodiments, the pack case 200 may further include crossbeams 240 that separate each of the cell assemblies 100. 【0094】 Multiple cell assemblies 100 can be arranged side by side as shown in Figure 5. In this arrangement, a cross beam 240 can be placed between pairs of cell assemblies 100 that are adjacent in the width direction, physically separating each cell assembly 100 from one another while simultaneously supporting the sides of the cell assemblies 100. 【0095】 The aforementioned anchoring space A is a space formed by the upper surface of the base plate 210 and the inner surface of the side beam 220, and the multiple cell assemblies 100 are anchored to the anchoring space A. 【0096】 The pack case 200 may further include a center beam 230 that crosses the center and connects to the base plate 210 so as to partition the anchoring space A, as shown in Figure 6. The center beam 230 partitions the anchoring space A of the pack case 200 into two, so as to physically separate the cell assemblies 100 that are anchored to each partitioned space. 【0097】 In some embodiments, the crossbeam 240 can be assembled with the cell assemblies 100 in the pack case 200, as shown in Figures 5 and 6. That is, the crossbeam 240 can be temporarily coupled to each adjacent cell assembly 100, and the crossbeam 240 can be coupled to the base plate 210 to secure the cell assemblies 100 to the pack case 200. 【0098】 In some embodiments, the crossbeam 240 can be coupled to the center beam 230 and side beams 220 separately from the cell assembly 100. That is, the crossbeam 240 interposed between the cell assemblies 100 may be coupled to the base plate 210, or to the center beam 230 and side beams 220. Specifically, both ends of the crossbeam 240 can be coupled to the side of the center beam 230 and the inner surface of the side beam 220, respectively. 【0099】 Therefore, the multiple cell assemblies 100 can be separated and secured in the spaces formed by the sections of the side beams 220, center beam 230, and cross beams 240. 【0100】 In some embodiments, the crossbeam 240 can prevent each cell assembly 100 from shaking or being damaged by external impacts. Therefore, the crossbeam 240 can be tightly coupled to the side of the cell stack 110 so as to leave no gap between the crossbeam 240 and the cell assembly 100, as shown in Figure 6. 【0101】 Figure 7 is a cross-sectional view of a pair of cell assemblies 100 with one of the crossbeams 240 in between in the battery pack of Figure 6. More specifically, Figure 7 shows a cross-section of the pair of cell assemblies 100 cut in the width direction of the cell assemblies 100, and is one embodiment in which an insulating pad 142 is interposed between the heat absorption pad 141 and the cell stack 110. 【0102】 Referring to Figure 7, the crossbeam 240 is in contact with the heat-absorbing pad 141 of the cell assembly 100 opposite it. That is, high-temperature heat transferred from either cell assembly 100 can first be transferred via the crossbeam 240 to the heat-absorbing pad 141 contained in the other cell assembly 100. The heat-absorbing pad 141 first absorbs the heat conducted from the crossbeam 240, and the insulating pad 142 adjacent to the heat-absorbing pad 141 prevents the transfer of excess heat that was not absorbed by the heat-absorbing pad 141 to the greatest extent possible. 【0103】 In one embodiment, although not shown, where a heat-absorbing pad 141 is interposed between the heat-insulating pad 142 and the cell stack 110, the heat-insulating pad 142 temporarily prevents heat from being conducted from the cross beam 240. Subsequently, the heat-absorbing pad 141 adjacent to the heat-insulating pad 142 absorbs the excess heat passing through the heat-insulating pad 142. 【0104】 The heat transfer prevention pad 140 of the present invention can reduce the heat that is transferred by the two methods described above. 【0105】 In a typical battery pack, the pair of cell assemblies 100 separated by a crossbeam 240 are located very close together. Therefore, if one of the cell assemblies 100 experiences thermal runaway, the high-temperature heat generated in the runaway cell assembly 100 can be transferred to the other cell assemblies 100 via the adjacent crossbeam 240. In contrast, in the battery pack of the present invention, the transfer of heat can be suppressed to some extent by the heat transfer prevention pads 140 provided on each cell assembly 100. 【0106】 Figure 8 is a perspective view showing a pack case 200 into which a plurality of cell assemblies 100 according to the second embodiment are mounted, and Figure 9 is a cross-sectional view showing a pair of cell assemblies 100 that are in close contact in the battery pack of Figure 8. 【0107】 The pack case 200 in Figure 8 above includes the cell assembly 100 according to the second embodiment shown in Figure 4 above. 【0108】 The cell assembly 100 further includes a pair of support members 150 provided on both sides of the cell stack 110 and coupled to the sides of the busbar frame 120 to support the plurality of cells 111. 【0109】 Therefore, any pair of adjacent cell assemblies 100 can be fixed together by the connection of their respective opposing support members 150. In this case, two adjacent support members 150 can be fixed together by screw connection using a connecting member such as a bolt. 【0110】 The battery pack shown in Figure 8, which includes the cell assemblies 100 and the pack case 200, has each cell assembly 100 containing support members 150 on both sides. Therefore, unlike the battery packs shown in Figures 5 and 6, two support members 150 are interposed between a pair of adjacent cell stacks 110. 【0111】 In some embodiments, the support member 150 not only improves the support force of the cell stack 110 but also plays a role in preventing heat transfer between each cell assembly 100. 【0112】 Referring to Figure 9, two support members 150 are interposed between a pair of cell stacks 110. In this case, if either cell stack 110 experiences thermal runaway, the high-temperature heat generated in the runaway cell stack 110 can be absorbed or blocked as it passes sequentially through the heat insulating pad 142, the heat absorbing pad 141, and the support members 150, and then sequentially moves through the support members 150, heat absorbing pad 141, and heat insulating pad 142 of the other cell assembly 100. 【0113】 Although not shown in the figures, the battery pack of the present invention further includes an upper case that connects to the pack case 200 so as to cover the upper part of the cell assembly 100 which is attached to the pack case 200. 【0114】 Specifically, the upper case is connected to the side beam 220 of the pack case 200, so that each cell assembly 100 located in the internal space can be isolated from the outside. 【0115】 The present invention has been described in more detail above with reference to the drawings and embodiments. However, the configurations described in the drawings or embodiments described herein are merely one embodiment of the present invention and do not represent the entire technical concept of the present invention. Therefore, there may be various equivalents and modifications that can be substituted for them at the time of filing. [Explanation of Symbols] 【0116】 100: Cell assembly 110: Cell stack 111: Cell 120: Busbar Frame 121: Bus bar 130: End plate 140: Heat transfer prevention pad 141: Heat absorption pad 142: Insulation pad 150: Support member 160: Compression pad 200: Pack Case 210: Base plate 220: Side beam 230: Center beam 240: Crossbeam A: Safety space

Claims

[Claim 1] A cell assembly, A cell stack in which multiple cells with protruding electrode leads are stacked, The cell stack includes a heat transfer resistant heat transfer prevention pad provided on both sides of the cell stack, wherein the heat transfer prevention pad includes a phase change material and a heat absorption pad that absorbs external heat, and a heat insulation pad with high heat resistance, and the heat transfer prevention pad is provided such that either the heat absorption pad or the heat insulation pad is attached to one surface of a cell stacked on the outermost edge of the cell stack. The plurality of cells are stacked in the width direction of the cell assembly, The cell stack further includes a pair of support members provided on each side to support the plurality of cells, The pair of support members prevent heat transfer between the cell assembly and other cell assemblies arranged adjacent to the cell assembly along the width direction of the cell assembly. A cell assembly in which the pair of support members are coupled to the sides of a busbar frame provided adjacent to the cell stack and to the sides of an end plate provided on the busbar frame. [Claim 2] The cell assembly according to claim 1, wherein the heat transfer prevention pad is interposed between the cell stack and the support member. [Claim 3] The cell assembly according to claim 1, wherein the cell stack further includes a compression pad interposed between any pair of cells among the plurality of cells. [Claim 4] A cell assembly according to any one of claims 1 to 3, A pack case including a space in which the cell assembly is secured, The aforementioned pack case is A base plate that supports the lower part of the cell assembly, A battery pack comprising: side beams coupled to the edge of the base plate so as to support the side of the cell assembly. [Claim 5] Multiple cell assemblies are secured in the aforementioned securing space. The battery pack according to claim 4, wherein the pack case further includes a crossbeam provided between any two adjacent cell assemblies. [Claim 6] The battery pack according to claim 5, wherein the crossbeam is tightly bonded to the side of each of the pair of cell assemblies so that there is no gap between the crossbeam and each of the pair of cell assemblies. [Claim 7] The battery pack according to claim 5, wherein the side surface of the crossbeam is in close contact with the heat-absorbing pads of the pair of cell assemblies facing the side surface of the crossbeam. [Claim 8] The battery pack according to claim 5, wherein the crossbeam is coupled to each adjacent cell assembly, and the crossbeam is coupled to the base plate so as to fix the cell assembly to the pack case. [Claim 9] Multiple cell assemblies are secured in the securing space, The battery pack according to claim 4, wherein two support members are interposed between any pair of adjacent cell assemblies, and the pair of cell assemblies are fixed by the two support members, which are positioned opposite each other, being connected to one another. [Claim 10] The battery pack according to claim 9, wherein the heat transfer prevention pad is interposed between the cell stack and the support member. [Claim 11] The battery pack according to claim 9, wherein the pair of support members are bonded to the heat transfer prevention pad in close contact with each support member so as to leave no gap between the support member and the heat transfer prevention pad.

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