Battery cell and battery assembly including the battery cell

Abstract

The technical idea of ​​the present invention provides a battery cell including an electrode assembly, a main body surrounding the electrode assembly, a sealing joint extending from one side of the main body in a first direction, the sealing joint including at least one notch portion, a cover sheet, and a first multi-function terminal block located at one end of the electrode assembly and including a first housing connected to the main body of the cover sheet.

Description

[Technical Field]

[0001] (Technical field) The present invention relates to a battery cell and a battery assembly including the battery cell.

[0002] (Reference to Related Application) This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0133551, dated October 6, 2023, and all contents disclosed in the documents of said Korean patent application are incorporated herein by reference. [Background technology]

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as energy sources for a variety of wireless devices, such as handsets, laptops, and wireless vacuum cleaners. In recent years, improvements in energy density and economies of scale have dramatically reduced the manufacturing cost per unit capacity of secondary batteries. As the driving range of battery electric vehicles (BEVs) has increased to the same level as fuel-powered vehicles, the primary use of secondary batteries has shifted from mobile devices to mobility.

[0004] As secondary batteries are used in mobility, there is a growing demand for their safety. Research into technologies to improve the safety of secondary batteries is essential, as a fire or other accident involving a secondary battery used in mobility could put the driver's life at risk. Summary of the Invention [Problem to be solved by the invention]

[0005] The technical problem that the present invention aims to achieve is to provide a battery cell and a battery assembly including the battery cell. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the technical idea of ​​the present invention provides a battery cell including an electrode assembly, a main body surrounding the electrode assembly, a sealing joint extending in a first direction from one side of the main body, the sealing joint including at least one notch portion, a cover sheet, and a first multifunctional terminal block (MTB) at one end of the electrode assembly and including a first housing connected to the main body of the cover sheet.

[0007] In an exemplary embodiment, the sealed joint is characterized by including a plurality of notches spaced apart along the first direction.

[0008] In an exemplary embodiment, the sealing joint includes a first edge coupled to the body portion and a second edge opposite the first edge; The at least one notch portion is characterized by extending from the second edge toward the first edge of the sealing joint.

[0009] In an exemplary embodiment, the adhesive sheet further includes a fastening tape that fastens the sealing joint to the main body portion of the cover sheet, the fastening tape being spaced apart from the at least one notch portion.

[0010] In an exemplary embodiment, the sealing joint includes a center and an edge, the fixing tape fixes the edge of the sealing joint to the main body of the cover sheet, and at least one notch is provided in the center of the sealing joint.

[0011] In an exemplary embodiment, the width of the sealing joint at the center of the sealing joint is characterized as being less than the width of the sealing joint at the edges of the sealing joint.

[0012] In an exemplary embodiment, the cover sheet further includes an elastic band that tightly attaches the edge of the sealing joint and the main body of the cover sheet to the first housing.

[0013] In an exemplary embodiment, the main body of the cover sheet is attached to the first housing.

[0014] In an exemplary embodiment, the first MTB is characterized by further including an external terminal attached to the first housing and coupled to an electrode lead of the electrode assembly.

[0015] In an exemplary embodiment, the first MTB further includes a venting disk attached to the first housing, the venting disk being configured to rupture to release gas when the internal pressure of the battery cell increases.

[0016] In an exemplary embodiment, the first MTB further includes a check valve attached to the first housing, the check valve being configured to open to discharge internal gas when the internal pressure of the battery cell is higher than a reference pressure, and to close again after the internal pressure is relieved.

[0017] In an exemplary embodiment, the device further includes a second MTB spaced apart in the first direction from the first MTB with the electrode assembly therebetween, and the second MTB includes a second housing connected to the main body portion of the cover sheet.

[0018] In order to solve the above-mentioned problems, the technical idea of ​​the present invention provides a battery assembly including a plurality of battery cells and a cooling pad arranged between the plurality of battery cells, wherein each of the plurality of battery cells includes an electrode assembly, a main body portion surrounding the electrode assembly, and a sealing joint extending in a first direction from one side of the main body portion, the sealing joint including a cover sheet including at least one notch portion, and a multifunctional terminal block (MTB) at one end of the electrode assembly and including a housing connected to the main body portion of the cover sheet.

[0019] In an exemplary embodiment, the main body portion of the cover sheet includes an upper portion that covers the upper surface of the electrode assembly and a side portion that covers the side surface of the electrode assembly, the cooling pad contacts the side portion of the main body portion of the cover sheet, and the sealed joint is connected to the upper portion of the main body portion of the cover sheet.

[0020] In an exemplary embodiment, the sealing joint further includes a fixing tape for fixing the edge of the sealing joint to the main body of the cover sheet, and at least one notch is provided in the center of the sealing joint. [Effects of the Invention]

[0021] According to an exemplary embodiment of the present invention, the sealed joint of the battery cell has a notch at its center, so that when the internal pressure of the battery cell increases, the seal is broken first at the center of the sealed joint, and high-temperature gas or flame generated inside the battery cell can be released upward through the center of the sealed joint where the seal is broken, thereby preventing heat transfer between adjacent battery cells and ultimately improving the safety of the battery assembly including the battery cell.

[0022] The effects that can be obtained from the exemplary embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood from the following description by a person having ordinary skill in the art to which the exemplary embodiments of the present disclosure belong. In other words, unintended effects accompanying the implementation of the exemplary embodiments of the present disclosure can also be derived from the exemplary embodiments of the present disclosure by a person having ordinary skill in the art. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a perspective view of a battery cell according to an exemplary embodiment of the present invention; [Figure 2] FIG. 2 is an exploded perspective view showing the battery cell of FIG. [Figure 3] 2 is a cross-sectional view showing a portion of the battery cell of FIG. 1. [Figure 4] FIG. 2 is a plan view showing a portion of the battery cell. [Figure 5a] 10A and 10B are perspective views showing a manufacturing method of a battery cell. [Figure 5b] 10A and 10B are perspective views showing a manufacturing method of a battery cell. [Figure 5c] 10A and 10B are perspective views showing a manufacturing method of a battery cell. [Figure 6] FIG. 2 is a plan view of a portion of a battery cell according to an exemplary embodiment of the present invention. [Figure 7] FIG. 1 is a perspective view of a battery assembly according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before that, it should be noted that the terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concept of the term to best describe his / her invention.

[0025] Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and there may be various equivalents and modifications that can replace them at the time of this application.

[0026] Furthermore, in the description of the present invention, if it is determined that a specific description of related publicly known configurations or functions may obscure the gist of the present invention, the detailed description will be omitted.

[0027] The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and therefore the shapes and sizes of components in the drawings may be exaggerated, omitted, or shown in a schematic manner for clearer explanation. Therefore, the sizes and proportions of each component do not completely reflect the actual sizes and proportions.

[0028] (First embodiment) Fig. 1 is a perspective view showing a battery cell 100 according to an exemplary embodiment of the present invention. Fig. 2 is an exploded perspective view showing the battery cell 100 of Fig. 1. Fig. 3 is a cross-sectional view showing a portion of the battery cell 100 of Fig. 1.

[0029] Referring to FIGS. 1 to 3, a battery cell 100 may include an electrode assembly 110, a multifunctional terminal block (MTB) 120, and a cover sheet .

[0030] The electrode assembly 110 may include a plurality of unit cells 111. Each of the unit cells 111 may have an electrode material coated on a metal foil that acts as a current collector. In an exemplary embodiment, the electrode assembly 110 is a stacked electrode assembly, and the unit cells 111 may be stacked on top of each other in a second direction (e.g., the X direction). The electrode assembly 110, which is composed of the plurality of unit cells 111, may have a generally rectangular parallelepiped shape. The electrode assembly 110 may have first and second side surfaces that are opposite to each other in the second direction (e.g., the X direction) and top and bottom surfaces that are opposite to each other in a third direction (e.g., the Z direction).

[0031] Each unit battery 111 may have a thin plate-shaped body extending in a first direction (e.g., Y direction). Each unit battery 111 may be a positive electrode unit battery or a negative electrode unit battery. In some embodiments, the plurality of unit batteries 111 may be formed by alternately stacking positive electrode unit batteries and negative electrode unit batteries one by one. The positive electrode unit batteries and the negative electrode unit batteries may be separated from each other by a separator. In some embodiments, the plurality of unit batteries 111 may be formed by alternately stacking positive electrode unit batteries and negative electrode unit batteries. The positive electrode unit batteries and the negative electrode unit batteries may be separated from each other by a separator.

[0032] The electrode assembly 110 may have electrode leads 116 at both ends in the first direction (e.g., Y direction). The electrode leads 116 may be electrically connected to electrode tabs of the plurality of unit cells 111. One or more electrode tabs may be connected to one electrode lead 116. In some embodiments, two or more electrode tabs may be connected to one electrode lead 116.

[0033] In some embodiments, the electrode assembly 110 may have two electrode leads 116 on one side and two electrode leads 116 on the other side. In this case, half of the unit batteries 111 included in the electrode assembly 110 may be coupled to one of the two electrode leads 116 on one side of the electrode assembly 110 and one of the two electrode leads 116 on the other side of the electrode assembly 110. The remaining half of the unit batteries 111 included in the electrode assembly 110 may be coupled to the other of the two electrode leads 116 on one side of the electrode assembly 110 and the other of the two electrode leads 116 on the other side of the electrode assembly 110. However, the present invention is not limited thereto.

[0034] In some embodiments, the electrode assembly 110 may have one or more than two electrode leads 116 on one side. In some embodiments, the electrode assembly 110 may have one or more than two electrode leads 116 on the other side.

[0035] An MTB 120 may be disposed at each end of the electrode assembly 110 in a first direction (e.g., Y direction). The MTBs 120 may be spaced apart in the first direction (e.g., Y direction) with the electrode assembly 110 interposed therebetween. For example, a first MTB may be provided at one end of the electrode assembly 110 in the first direction (e.g., Y direction), and a second MTB may be provided at the other end of the electrode assembly 110 in the first direction (e.g., Y direction). In this case, one of the first MTB and the second MTB may be electrically connected to the positive electrode side of the electrode assembly 110, and the other may be electrically connected to the negative electrode side of the electrode assembly 110. The first MTB and the second MTB may have substantially the same or similar configurations, differing only in electrical polarity.

[0036] The MTB 120 may include an MTB housing 122, an external terminal 124 mounted within the MTB housing 122, a bus bar 125, a rupture disk 126, and a check valve 128. In this disclosure, the two MTBs 120 may be referred to as a first MTB and a second MTB, and the MTB housing 122 of the first MTB may be referred to as a first MTB housing, and the MTB housing 122 of the second MTB may be referred to as a second MTB housing.

[0037] The MTB housing 122 can be made of a relatively rigid material, such as a metal, and can define the appearance of the MTB 120. In some embodiments, the MTB housing 122 can be made of aluminum (Al), nickel (Ni), iron (Fe), cobalt (Co), chromium (Cr), manganese (Mn), or an alloy containing one or more of these.

[0038] The MTB housing 122 may include through holes for exposing the external terminals 124 to the outside. The through holes of the MTB housing 122 may be provided in the MTB housing 122 so that the external terminals 124 are exposed to the outside in the first direction (e.g., the Y direction). The shape of the through holes may be configured to match the shape of an outer edge of the portion of the external terminals 124 exposed to the outside.

[0039] The external terminal 124 is accommodated in the MTB housing 122 and may be inserted and attached to a through-hole of the MTB housing 122. The external terminal 124 may be made of a metal or metal alloy with low electrical resistance, such as copper (Cu), aluminum (Al), nickel (Ni), iron (Fe), platinum (Pt), manganese (Mn), or an alloy containing one or more of these.

[0040] In some embodiments, the exposed surface of the external terminal 124 exposed to the outside from the MTB housing 122 may be flat. In some embodiments, the exposed surface of the external terminal 124 may have a flat surface extending perpendicular to the first direction (e.g., Y direction).

[0041] In some embodiments, an electrically insulating spacer may be provided between the external terminal 124 and the MTB housing 122 so that the external terminal 124 is electrically insulated from the MTB housing 122 .

[0042] The venting disk 126 may be attached to a through-hole provided in the MTB housing 122. The venting disk 126 may be configured to burst when the internal pressure of the battery cell 100 rises excessively, thereby discharging gas that causes the excessively high internal pressure. If the venting disk 126 bursts due to a thermal event occurring inside the battery cell 100, it will not return to its original state. The venting disk 126 may be inserted and attached to a through-hole in the MTB housing 122. The venting disk 126 may be any venting disk 126 known in the art and is not particularly limited. The venting disk 126 may be provided on at least one of the two MTBs 120 at both ends of the battery cell 100.

[0043] The check valve 128 may be mounted in a through-hole provided in the MTB housing 122. The check valve 128 may be configured to open and close a gas discharge passage according to the internal pressure of the battery cell 100. The check valve 128 may be configured to open the gas discharge passage to discharge internal gas when the internal pressure of the battery cell 100 becomes higher than a reference pressure, and to close the gas discharge passage again when the internal pressure is relieved by the gas being discharged. The check valve 128 may close the gas discharge passage to block gas discharge when the internal pressure of the battery cell 100 becomes equal to or lower than the reference pressure. The check valve 128 may be inserted and mounted in a through-hole provided in the MTB housing 122. The check valve 128 does not have any parts that may burst due to the gas being discharged, and therefore may be restored to its original state after the internal gas is discharged. The check valve 128 may be provided in at least one of the two MTBs 120 at both ends of the battery cell 100.

[0044] In some embodiments, the MTB 120 may include an electrolyte inlet 127 through which an electrolyte can be injected. The electrolyte inlet 127 may be provided in the MTB housing 122. In some embodiments, the electrolyte inlet 127 may be provided in only one of the two MTBs 120 at both ends of the battery cell 100. The electrolyte injected through the electrolyte inlet 127 may be an electrolyte used for a typical lithium secondary battery and is not particularly limited.

[0045] The bus bar 125 may electrically connect the external terminal 124 to the electrode lead 116 of the electrode assembly 110. The bus bar 125 may be mounted within the MTB housing 122.

[0046] The bus bar 125 may be provided to make surface contact with the external terminal 124. The bus bar 125 may be made of a metal material having low electrical resistance. In some embodiments, the bus bar 125 may be made of copper (Cu), nickel (Ni), aluminum (Al), iron (Fe), cobalt (Co), platinum (Pt), molybdenum (Mo), tin (Sn), palladium (Pd), or an alloy containing one or more of these.

[0047] In exemplary embodiments, the material of the busbars 125 and the material of the external terminals 124 may be different from one another. In some embodiments, the busbars 125 include copper and the external terminals 124 include aluminum. In some exemplary embodiments, the material of the busbars 125 and the material of the external terminals 124 may be the same.

[0048] The bus bar 125 may be configured to make surface contact with the electrode leads 116 of the electrode assembly 110. In some embodiments, the bus bar 125 may be coupled to the electrode leads 116 by welding.

[0049] In some embodiments, the bus bar 125 may include a flat central portion 125c extending generally along the second direction (e.g., the X direction) and the third direction (e.g., the Z direction), and edge portions 125e bent and extending from the central portion 125c. The central portion 125c may be in contact with the external terminal 124, and the edge portions 125e may be in contact with the electrode leads 116 of the electrode assembly 110.

[0050] The bus bar 125 may include two edge portions 125e facing each other in a second direction (e.g., the X direction), and the two edge portions 125e may have a generally flat plate shape extending along a first direction (e.g., the Y direction) and a third direction (e.g., the Z direction), respectively. One of the two edge portions 125e may extend in the first direction (e.g., the Y direction) from one end of the center portion 125c along the second direction (e.g., the X direction), and the other of the two edge portions 125e may extend in the first direction (e.g., the Y direction) from the other end of the center portion 125c along the second direction (e.g., the X direction). The center portion 125c and the two edge portions 125e may be configured to have a U-shaped cross section. When the two edge portions 125e are referred to as the first edge portion and the second edge portion, the outer surface of the first edge portion can have a plane that makes surface contact with the first electrode lead of the electrode assembly 110, and the outer surface of the second edge portion can have a plane that makes surface contact with the second contact lead of the electrode assembly 110.

[0051] In some embodiments, the electrode lead 116 may include a pre-bended portion that is bent at a portion that does not contact the bus bar 125. The pre-bended portion may prevent stress from concentrating at a specific portion of the electrode lead 116 due to an external force applied to the electrode assembly 110, thereby improving safety.

[0052] The cover sheet 130 may provide a receiving space for receiving the electrode assembly 110. The cover sheet 130 may include a body portion 131 surrounding the electrode assembly 110 and a sealing joint portion 133 extending or protruding from the body portion 131.

[0053] The body portion 131 of the cover sheet 130 may surround the electrode assembly 110 to form an accommodation space in which the electrode assembly 110 is accommodated. The body portion 131 of the cover sheet 130 may be connected to the MTB housing 122 of the MTB 120. For example, a first edge of the body portion 131 of the cover sheet 130 may be attached to the first housing of the first MTB, and a second edge of the body portion 131 of the cover sheet 130 may be attached to the second housing of the second MTB. The first edge of the body portion 131 of the cover sheet 130 may be in continuous contact with the first housing along the periphery of the first MTB, and the second edge of the body portion 131 of the cover sheet 130 may be in continuous contact with the second housing of the second MTB along the periphery. The main body portion 131 of the cover sheet 130 may include a first side portion facing the first side of the electrode assembly 110 and the first sides of the two MTB housings 122, a second side portion facing the second side of the electrode assembly 110 and the second sides of the two MTB housings 122, an upper portion facing the upper surface of the electrode assembly 110 and the upper surfaces of the two MTB housings 122, and a lower portion facing the lower surface of the electrode assembly 110 and the lower surfaces of the two MTB housings 122. The main body portion 131 of the cover sheet 130 may form an accommodation space for the battery cell 100 in which the electrode assembly 110 is accommodated together with the MTB housings 122 of the two MTBs 120.

[0054] The sealed joint 133 may seal the accommodation space of the body 131 in which the electrode assembly 110 is accommodated. The sealed joint 133 may be connected to an upper portion of the body 131 and extend in a first direction (e.g., the Y direction). The sealed joint 133 may be a joint formed by joining a first portion 138 and a second portion 139 of the cover sheet 130. For example, to manufacture the cover sheet 130, the electrode assembly 110 may be surrounded by a single cover sheet 130, and then the first portion 138 and the second portion 139 of the cover sheet 130 may be joined to form the sealed joint 133.

[0055] In an exemplary embodiment, the cover sheet 130 may be a laminate sheet including one or more resin layers and one or more metal layers, which may be laminated together.

[0056] According to an exemplary embodiment of the present invention, the battery cell 100 accommodates all of the units having respective functions, such as the external terminal 124, the venting disk 126, the check valve 128, the electrolyte injection port 127, and the bus bar 125, within the MTB 120, so that the battery cell 100 itself has a function equivalent to that of a general battery module. Therefore, the battery cell 100 according to the embodiment can have a high degree of flexibility and compatibility, and is advantageous for realizing a cell-to-pack.

[0057] FIG. 4 is a plan view showing a portion of the battery cell 100. As shown in FIG.

[0058] 4 in conjunction with FIG. 1 , the sealing joint 133 may include at least one notch portion 134. When the sealing joint 133 has a first edge 1331 connected to the main body portion 131 and a second edge 1333 opposite the first edge 1331, the notch portion 134 may extend from the second edge 1333 of the sealing joint 133 toward the first edge 1331. The first edge 1331 of the sealing joint 133 is a boundary between the sealing joint 133 and the main body portion 131 and may extend in a first direction (e.g., the Y direction) from one end to the other end of the main body portion 131. In an exemplary embodiment, the sealing joint 133 may include a plurality of notches 134 spaced apart from each other along the first direction (e.g., the Y direction). Although FIG. 4 illustrates the sealing joint 133 as including two notches 134, the sealing joint 133 may include three or more notches 134.

[0059] The sealing joint 133 may include two edge portions 133e in a first direction (e.g., the Y direction) and a center portion 133c between the two edge portions 133e. In the sealing joint 133, the length of each edge portion 133e in the first direction (e.g., the Y direction) may be 10% to 40%, 15% to 35%, or 20% to 30% of the overall length of the sealing joint 133 in the first direction (e.g., the Y direction).

[0060] In the exemplary embodiment, the battery cell 100 may include fixing tapes 141 for fixing the edge 133 e of the sealing joint 133 to the main body portion 131. Each fixing tape 141 may fix a corresponding edge 133 e of the sealing joint 133 to the main body portion 131. A portion of each fixing tape 141 may be attached to the edge 133 e of the sealing joint 133, and another portion of each fixing tape 141 may be attached to the main body portion 131.

[0061] The fixing tape 141 may be spaced apart from the notch portion 134 of the sealing joint 133. That is, the fixing tape 141 may not cover the notch portion 134 of the sealing joint 133. The fixing tape 141 may fix the edge portion 133e of the sealing joint 133 to the main body portion 131 of the cover sheet 130, and the notch portion 134 may be provided in the center portion 133c of the sealing joint 133 that is not fixed to the main body portion 131 of the cover sheet 130 by the fixing tape 141.

[0062] In an exemplary embodiment, the battery cell 100 may include elastic bands 145 for tightly fixing the cover sheet 130 to the MTB housing 122. Each elastic band 145 may fix the corresponding edge 133e of the sealing joint 133 and the main body portion 131 to the corresponding MTB housing 122. Each elastic band 145 may have a ring shape that extends to surround the MTB housing 122.

[0063] The sealing strength of the sealing joint 133 of the cover sheet 130 may be relatively weak in the region where the notch 134 is disposed. In this case, when the internal pressure of the battery cell 100 increases, the seal is first broken at the center 133c of the sealing joint 133 where the notch 134 is provided, and high-temperature gas or flame generated inside the battery cell 100 can be discharged upward through the center 133c of the sealing joint 133 where the seal is broken. According to the present invention, the high-temperature gas or flame generated inside the battery cell 100 is discharged in a concentrated manner through the center 133c of the sealing joint 133 of the cover sheet 130, thereby preventing heat transfer between adjacent battery cells 100 and ultimately improving the safety of the battery assembly including the battery cells 100.

[0064] 5a to 5c are perspective views showing a manufacturing method of the battery cell 100. FIG.

[0065] 5a, a cover sheet 130 is formed and attached to the MTB housings 122 of two MTBs 120. For example, a single sheet can be attached around the MTB housings 122 of the two MTBs 120, and a first portion and a second portion of the single sheet can be joined. Then, a portion of the joined body where the first and second portions of the single sheet are joined can be removed to form the cover sheet 130 including a sealed joint 133 with a notch 134.

[0066] 5b, elastic bands 145 are used to securely fasten the edges of the cover sheet 130 around the MTB housing 122. The elastic bands 145 allow the sealing joint 133 to be tightly attached to the outer surface of the main body portion 131.

[0067] 5c, the edges of the sealing joint 133 are fixed to the main body 131 using a fixing tape 141. The fixing tape 141 allows the two edges of the sealing joint 133 to be fixed to the outer surface of the main body 131.

[0068] (Second embodiment) Fig. 6 is a plan view showing a portion of a battery cell according to an exemplary embodiment of the present invention. The battery cell shown in Fig. 6 will be described below, focusing on the differences from the battery cell 100 described with reference to Figs. 1 to 4.

[0069] 6, the width of the sealing joint 133 may vary depending on the position of the sealing joint 133 along a first direction (e.g., the Y direction). The width of the sealing joint 133 may refer to the length of the sealing joint 133 along a direction perpendicular to the first direction (e.g., the Y direction). Alternatively, when the sealing joint 133 has a first edge 1331 connected to the main body 131 and a second edge 1333 opposite the first edge 1331, the width of the sealing joint 133 may refer to the distance between the first edge 1331 and the second edge 1333 of the sealing joint 133.

[0070] In an exemplary embodiment, when the sealing joint 133 has a minimum width W1 at the first point, the first point of the sealing joint 133 may be within the center 133c of the sealing joint 133. In an exemplary embodiment, the sealing joint 133 may have a maximum width W2 at an end along the first direction (e.g., the Y direction). In an exemplary embodiment, the width of the sealing joint 133 may increase with increasing distance from the first point.

[0071] In an exemplary embodiment, the profile of the second edge 1333 of the sealing joint 133 can include multiple straight lines, for example, two straight lines.

[0072] In exemplary embodiments, the minimum width W1 of the sealing joint 133 may be 10% to 90%, 15% to 85%, 20% to 80%, 25% to 75%, or 30% to 70% of the maximum width W2 of the sealing joint 133. In exemplary embodiments, the minimum width W1 of the sealing joint 133 may be 3 mm or greater. In exemplary embodiments, the maximum width W2 of the sealing joint 133 may be equal to or less than the width of the upper portion of the main body portion 131 along the second direction (e.g., the X direction) or the width of the MTB housing 122 along the second direction (e.g., the X direction).

[0073] In an exemplary embodiment, within the edge 133e of the sealing joint 133, the width of the sealing joint 133 may decrease as it moves away from the end of the sealing joint 133 along the first direction (eg, the Y direction).

[0074] The sealing strength of each region of the sealing joint 133 of the cover sheet 130 may be proportional to the width of the sealing joint 133 in that region. In the embodiment, the sealing joint 133 has the smallest width at its center 133c. Therefore, when the internal pressure of the battery cell increases, the seal is first broken at the center 133c of the sealing joint 133, and high-temperature gas or flame generated inside the battery cell can be released upward through the center 133c of the sealing joint 133 where the seal is broken. According to the present invention, the high-temperature gas or flame generated inside the battery cell is exhausted in a concentrated manner through the center 133c of the sealing joint 133 of the cover sheet 130, thereby preventing heat transmission between adjacent battery cells and ultimately improving the safety of the battery assembly including the battery cells.

[0075] (Third embodiment) FIG. 7 is a perspective view of a battery assembly 10 according to an exemplary embodiment of the present invention.

[0076] 7, the battery assembly 10 may include a plurality of battery cells 100 and a plurality of cooling pads 200. The plurality of battery cells 100 may be arranged in a second direction (e.g., the X direction), and a cooling pad 200 may be disposed between two adjacent battery cells 100.

[0077] The cooling pad 200 may be disposed between two adjacent battery cells 100 in a first direction (e.g., the Y direction). The two battery cells 100 may be spaced apart in the first direction (e.g., the Y direction) by the cooling pad 200. The cooling pad 200 may be attached to a side of the main body portion 131 of the cover sheet 130 of the adjacent battery cells 100 and / or the MTB housing 122.

[0078] The cooling pad 200 may be configured to cool adjacent battery cells 100. In some embodiments, the cooling pad 200 may be configured to cool the battery cells 100 by absorbing heat from the adjacent battery cells 100. For example, the cooling pad 200 may include an endothermic material layer therein. For example, the endothermic material layer of the cooling pad 200 may include an absorbent material such as a super absorbent polymer (SAP). The cooling pad 200 may be disposed between adjacent battery cells 100 in a first direction (e.g., the Y direction) and function as a thermal barrier for thermally isolating the battery cells 100. Since the cooling pad 200 is disposed between the plurality of battery cells 100, even if one of the plurality of battery cells 100 ignites, the heat transfer between the ignited battery cell 100 and the other battery cells 100 may be blocked or suppressed by the cooling pad 200.

[0079] Furthermore, the cooling pad 200 is configured to have a predetermined rigidity due to an internal support structure and / or an internal filler, and can prevent or suppress deformation of the battery cells 100 due to swelling. Furthermore, the cooling pad 200 is configured to have a predetermined elasticity due to an internal support structure and / or an internal filler, and can be configured to be elastically deformed in a first direction (e.g., Y direction) that is the arrangement direction of the battery cells 100. By elastically deforming in the first direction (e.g., Y direction), the cooling pad 200 can function as a buffer pad against deformation of the battery cells 100 (e.g., deformation of the battery cells 100 due to swelling).

[0080] According to the exemplary embodiment of the present invention, the cooling pad 200 is disposed between adjacent battery cells 100 to function as a thermal barrier and a buffer, thereby preventing heat transfer between the battery cells 100 and improving the structural safety of the battery cells 100. This improves the safety and reliability of the battery assembly 10 including the battery cells 100.

[0081] According to an exemplary embodiment, both sides of each battery cell 100 may be in contact with the cooling pad 200, and the bottom of each battery cell 100 may be in contact with an external heat sink. In this case, high-temperature gas or flame generated in each battery cell 100 may be discharged upward through the center 133c of the sealing joint 133, which has a relatively low sealing strength. According to the present invention, the high-temperature gas or flame generated inside the battery cell 100 is discharged in a concentrated manner through the center 133c of the sealing joint 133 of the cover sheet 130, thereby preventing heat transfer between adjacent battery cells 100 and ultimately improving the safety of the battery assembly 10 including the battery cells 100.

[0082] The present invention has been described in more detail above with reference to the drawings and embodiments, etc. However, the configurations shown in the drawings or embodiments in this specification are merely one embodiment of the present invention and do not represent all of the technical ideas of the present invention, and therefore, there may be various equivalents and modifications that can replace them at the time of filing this application.

Claims

1. an electrode assembly; a cover sheet including a body portion surrounding the electrode assembly and a sealing joint portion extending in a first direction from one side of the body portion, the sealing joint portion including at least one notch portion; a first multi-function terminal block (first MTB) at one end of the electrode assembly and including a first housing coupled to the body portion of the cover sheet; Battery cell.

2. The battery cell of claim 1 , wherein the sealed joint includes a plurality of notches spaced apart from one another along the first direction.

3. the sealing joint includes a first edge connected to the body portion and a second edge opposite the first edge; the at least one notch extends from the second edge toward the first edge of the sealing joint; The battery cell of claim 1 .

4. a fastening tape for fastening the sealing joint to the main body portion of the cover sheet; the fixing tape is spaced from the at least one notch portion; The battery cell of claim 1 .

5. the sealed joint includes a center and an edge; the fixing tape fixes the edge of the sealing joint to the main body of the cover sheet; the at least one notch is provided in the center of the sealing joint; The battery cell of claim 4 .

6. The battery cell of claim 5 , wherein a width of the sealing joint at a center of the sealing joint is smaller than a width of the sealing joint at an edge of the sealing joint.

7. The battery cell according to claim 1 , further comprising an elastic band that tightly attaches an edge of the sealing joint and the body portion of the cover sheet to the first housing.

8. The battery cell of claim 1 , wherein the body portion of the cover sheet is attached to the first housing.

9. The battery cell of claim 1 , wherein the first MTB is mounted in the first housing and further comprises an external terminal connected to an electrode lead of the electrode assembly.

10. 2. The battery cell of claim 1, wherein the first MTB further includes a venting disk attached to the first housing, the venting disk configured to burst and release gas when an internal pressure of the battery cell increases.

11. The first MTB further includes a check valve mounted in the first housing; The check valve is configured to open to discharge internal gas when the internal pressure of the battery cell is higher than a reference pressure, and to close again after the internal pressure is relieved. The battery cell of claim 1 .

12. 2. The battery cell of claim 1, further comprising a second multi-function terminal block (second MTB) spaced apart in the first direction from the first MTB with the electrode assembly therebetween, the second MTB comprising a second housing connected to the body portion of the cover sheet.

13. a plurality of battery cells; a cooling pad disposed between the plurality of battery cells.

1. A battery assembly comprising: Each of the plurality of battery cells an electrode assembly; a cover sheet including a body portion surrounding the electrode assembly and a sealing joint portion extending in a first direction from one side of the body portion, the sealing joint portion including at least one notch portion; a multifunction terminal block (MTB) at one end of the electrode assembly and including a housing coupled to the body portion of the cover sheet; Battery assembly.

14. the main body of the cover sheet includes an upper portion that covers an upper surface of the electrode assembly and a side portion that covers a side surface of the electrode assembly, the cooling pad contacts the side of the main body portion of the cover sheet; the sealing joint is connected to the top of the body portion of the cover sheet; 14. The battery assembly of claim 13.

15. a fixing tape for fixing an edge of the sealing joint to the main body portion of the cover sheet; the at least one notch is provided in a central portion of the sealing joint; 14. The battery assembly of claim 13.

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