Secondary battery

Abstract

Provided is a secondary battery comprising: a stack-type electrode assembly including a plurality of unit batteries stacked in a first direction, and an electrode lead at either end of the stack-type electrode assembly in a second direction perpendicular to the first direction; a multifunctional terminal block (MTB) provided at either the end of the stack-type electrode assembly; and a laminate sheet surrounding the side surface of the stack-type electrode assembly, wherein the MTB includes: an electrode terminal unit electrically connected to the electrode lead of the stack-type electrode assembly; and a rupture disk that ruptures when internal pressure increases, to discharge gas.

Description

secondary batteries

[0001] The present invention relates to a secondary battery, and more particularly, to a secondary battery that is advantageous in implementing a large-capacity cell, is advantageous in configuring a battery pack due to its high degree of freedom and compatibility, and has improved safety.

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0075259, filed June 13, 2023, the entire disclosure of which is incorporated herein by reference.

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various wireless devices, including handsets, laptops, and cordless vacuum cleaners. Recently, improved energy density and economies of scale have dramatically reduced the per-unit manufacturing cost of secondary batteries. Furthermore, as the range of battery electric vehicles (BEVs) has increased to match that of fuel-powered vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

[0004] Meanwhile, demand for large-capacity battery packs for electric vehicles and other applications is increasing. Large-capacity battery packs installed in automobiles are expected to increase capacity and enhance safety.

[0005] The technical problem to be achieved by the present invention is to provide a secondary battery that is advantageous not only in implementing a large-capacity cell, but also in configuring a battery pack due to a high degree of freedom and compatibility, and has improved safety.

[0006] In order to achieve the above technical problem, the present invention provides a secondary battery including a stacked electrode assembly in which a plurality of unit cells are stacked in a first direction and have electrode leads at both ends in a second direction perpendicular to the first direction; a multifunctional terminal block (MTB) provided at both ends of the stacked electrode assembly; and a laminate sheet covering a side surface of the stacked electrode assembly, wherein the MTB includes an electrode terminal portion electrically connected to the electrode leads of the stacked electrode assembly; and a venting disk that ruptures when internal pressure increases to discharge gas.

[0007] In some embodiments, the MTB further includes a check valve, and the check valve may be configured to open to discharge internal gas when the internal pressure of the secondary battery is higher than a certain pressure, and to close again after the internal pressure is relieved.

[0008] In some embodiments, the laminate sheet may at least partially cover a side surface of the MTB.

[0009] In some embodiments, the laminate sheet may be fused to a side surface of the MTB.

[0010] In some embodiments, the MTB may further include an electrolyte inlet configured to inject an electrolyte.

[0011] In some embodiments, the laminate sheet may be configured to surround a side surface of the stacked electrode assembly and then be fused to one side of the stacked electrode assembly to enclose the side surface of the stacked electrode assembly.

[0012] In some embodiments, the laminate sheet may include a flexible metal layer; an inner resin layer provided on one side of the metal layer; and an outer resin layer provided on the other side of the metal layer, wherein the inner resin layers are fused together so that the laminate sheet wraps around a side surface of the stacked electrode assembly.

[0013] In some embodiments, the inner resin layer may comprise cast polypropylene (CPP).

[0014] In some embodiments, the inner resin layer may be fused to a side surface of the MTB.

[0015] In some embodiments, the MTB may further include a bus bar electrically connecting the electrode leads of the stacked electrode assembly to the electrode terminal portion.

[0016] Another aspect of the present invention provides a secondary battery including a stacked electrode assembly in which a plurality of unit cells are stacked in a first direction, extending in a second direction perpendicular to the first direction and having electrode leads at ends; a multifunctional terminal block (MTB) coupled to the electrode leads of the stacked electrode assembly; and a laminate sheet wrapping the stacked electrode assembly together with the MTB, wherein the MTB includes an electrode terminal portion electrically connected to the electrode leads of the stacked electrode assembly; and a bus bar electrically connecting the electrode leads and the electrode terminal portion.

[0017] In some embodiments, the MTB further includes an MTB housing that accommodates the electrode terminal portion and the bus bar, and the electrode terminal portion can be exposed to the outside through a through hole provided in the MTB housing.

[0018] In some embodiments, the stacked electrode assembly may extend in a second direction perpendicular to the first direction, and the through hole may be provided at an end of the MTB housing facing the second direction.

[0019] In some embodiments, the laminate sheet surrounds a side surface of the stacked electrode assembly and has a lamination portion in a third direction of the stacked electrode assembly, and the laminate sheet can at least partially cover a side surface of the MTB.

[0020] In some embodiments, the bus bar may include a center portion having a planar shape extending horizontally in the first direction and configured to be in surface contact with the electrode terminal portion; and an edge portion extending in a bent manner from the center portion.

[0021] The secondary battery according to embodiments of the present invention is not only advantageous in implementing a large-capacity cell, but is also advantageous in configuring a battery pack due to its high degree of freedom and compatibility, and can have improved safety.

[0022] The effects that can be obtained from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

[0023] Figure 1a is a perspective view showing the main part of a secondary battery according to one embodiment of the present invention.

[0024] Figure 1b is a partial perspective view showing an enlarged portion of a part of the secondary battery of Figure 1a.

[0025] Figure 2 is a schematic perspective view showing the appearance of the laminate sheet removed from the secondary battery of Figure 1.

[0026] Figure 3 is a schematic diagram showing a cross-section of the first MTB cut along a plane perpendicular to the third direction and passing through the electrode terminal portion.

[0027] Figure 4 is a partially exploded perspective view showing a method of bonding laminate sheets of a secondary battery according to one embodiment of the present invention.

[0028] Figure 5 is a partial cross-sectional view of a laminate sheet according to one embodiment of the present invention.

[0029] Figure 6a is a perspective view showing a main part of a secondary battery according to one embodiment of the present invention.

[0030] Figure 6b is a partial perspective view showing an enlarged portion of a part of the secondary battery of Figure 6a.

[0031] Figure 7 is a side view of a secondary battery according to another embodiment of the present invention.

[0032] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments of the present invention may be modified in various different forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. It is preferable to interpret that the embodiments of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art. Like numbers refer to like elements throughout. Furthermore, various elements and areas in the drawings are schematically drawn. Therefore, the present invention is not limited by the relative sizes or spacings depicted in the accompanying drawings.

[0033] While terms like "first" and "second" may be used to describe various components, these components are not limited by these terms. These terms are used solely to distinguish one component from another. For example, a first component could be referred to as a "second component," and vice versa, without departing from the scope of the present invention.

[0034] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the inventive concept. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the expressions "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, operations, components, parts, or combinations thereof.

[0035] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Furthermore, it is to be understood that commonly used terms, such as those defined in dictionaries, should be interpreted to have a meaning consistent with their meaning within the relevant technical context, and should not be interpreted in an overly formal sense unless explicitly defined herein.

[0036] In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

[0037] In the accompanying drawings, variations in the shapes depicted may be expected, for example, depending on manufacturing techniques and / or tolerances. Therefore, embodiments of the present invention should not be construed as being limited to the specific shapes of the regions depicted herein, but should include, for example, changes in shapes resulting from the manufacturing process. All terms "and / or" used herein include each and every combination of one or more of the mentioned components. In addition, the term "substrate" used herein may mean the substrate itself, or a laminated structure including the substrate and a predetermined layer or film formed on the surface thereof. In addition, the "surface of the substrate" in this specification may mean the exposed surface of the substrate itself, or the outer surface of a predetermined layer or film formed on the substrate.

[0038]

[0039] (Example 1)

[0040] Fig. 1a is a perspective view showing the main part of a secondary battery (100) according to one embodiment of the present invention. Fig. 1b is a partial perspective view showing an enlarged portion of a part of the secondary battery (100) of Fig. 1a. Fig. 2 is a schematic perspective view showing the secondary battery (100) of Fig. 1a with the laminate sheet (130) removed.

[0041] In the drawings below, the secondary battery (100) is illustrated as being defined in a vertical coordinate system defined by a first direction along the X-axis, a second direction along the Y-axis, and a third direction along the Z-axis, which are perpendicular to each other, but the first direction, the second direction, and the third direction are not particularly limited as long as they are relatively perpendicular to each other.

[0042] Referring to FIGS. 1a to 2, the secondary battery (100) includes a stacked electrode assembly (110), a multifunctional terminal block (MTB) (120a, 120b), and a laminate sheet (130).

[0043] The stacked electrode assembly (110) may include a plurality of unit cells (111) stacked in a first direction (e.g., X-axis direction). Each of the unit cells (111) may have an electrode material applied on a metal foil that acts as a current collector.

[0044] Each of the unit cells (111) may have a thin plate-shaped body extending in a second direction (e.g., the Y-axis direction). Each of the unit cells (111) may be a positive electrode unit cell or a negative electrode unit cell. In some embodiments, the plurality of unit cells (111) may be formed by alternately stacking positive electrode unit cells and negative electrode unit cells one by one. The positive electrode unit cell and the negative electrode unit cell may be separated from each other by a separator.

[0045] In some other embodiments, the plurality of unit batteries (111) may be formed by alternately stacking a plurality of positive unit batteries and a plurality of negative unit batteries. The plurality of positive unit batteries and the plurality of negative unit batteries may be separated from each other by a separator.

[0046] The stacked electrode assembly (110) may have electrode leads (116) at both ends in the second direction (e.g., Y-axis 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).

[0047] In some embodiments, the stacked 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 plurality of unit cells (111) included in the stacked electrode assembly (110) may be coupled to the first electrode lead on one side and coupled to the second electrode lead on the other side. In addition, the remaining half of the plurality of unit cells (111) included in the stacked electrode assembly (110) may be coupled to the third electrode lead on one side and coupled to the fourth electrode lead on the other side. However, the present invention is not limited thereto.

[0048] In some embodiments, the stacked electrode assembly (110) may have one or more electrode leads on one side. In some embodiments, the stacked electrode assembly (110) may have one or more electrode leads on the other side.

[0049] A first MTB (120a) may be provided at one end of the stacked electrode assembly (110) in the second direction (e.g., Y-axis direction), and a second MTB (120b) may be provided at the other end. One of the first MTB (120a) and the second MTB (120b) may be electrically connected to the positive electrode side of the stacked electrode assembly (110), and the other may be electrically connected to the negative electrode side of the stacked electrode assembly (110). The second MTB (120b) may have substantially the same configuration as the first MTB (120a) except for the polarity. Hereinafter, the first MTB (120a) will be described, but a person skilled in the art will be able to understand the configuration of the second MTB (120b) therefrom.

[0050] The above first MTB (120a) may include an MTB housing (122), an electrode terminal portion (124) accommodated within the MTB housing (122), and a bus bar (125) (see FIG. 3) electrically connecting the electrode terminal portion (124) and the electrode lead (116).

[0051] The above MTB housing (122) may be made of a material having relatively high rigidity, such as metal, and defines the appearance of the first MTB (120a). In some embodiments, the MTB housing (122) may be made of aluminum (Al), nickel (Ni), iron (Fe), cobalt (Co), chromium (Cr), manganese (Mn), or an alloy containing one or more of these.

[0052] The MTB housing (122) may include a through hole (122h) exposing the electrode terminal portion (124) described below. The through hole (122h) may be provided in the MTB housing (122) so that the electrode terminal portion (124) is exposed toward the second direction (e.g., Y-axis direction). Therefore, the through hole (122h) may be provided on a plane perpendicular to the second direction (e.g., Y-axis direction) of the MTB housing (122). In addition, the through hole (122h) may have an opening that is open in the longitudinal direction of the electrode assembly (110). The shape of the through hole (122h) may be configured to match the outer shape of the portion where the electrode terminal portion (124) is exposed to the outside.

[0053] A person skilled in the art will understand that the first MTB (120a) may further include, as necessary, a through hole for a venting disc, a through hole for a check valve, and a through hole for an electrolyte injection port, as described later.

[0054] The electrode terminal portion (124) is accommodated within the MTB housing (122) and can be exposed through the through hole (122h). The electrode terminal portion (124) can be made of a metal or metal alloy having low electrical resistance, and can be, for example, an alloy containing copper (Cu), aluminum (Al), nickel (Ni), iron (Fe), platinum (Pt), manganese (Mn), or one or more thereof.

[0055] In some embodiments, the exposed surface of the electrode terminal portion (124) facing outward from the MTB housing (122) may be a plane. In some embodiments, the exposed surface may have a plane extending perpendicular to the second direction (e.g., the Y-axis direction).

[0056] In some embodiments, an electrically insulating spacer may be provided between the electrode terminal portion (124) and the MTB housing (122) so that the electrode terminal portion (124) is electrically insulated from the MTB housing (122).

[0057] In some embodiments, the first MTB (120a) may include a venting disk (126) configured to rupture when the internal pressure of the secondary battery (100) excessively increases, thereby releasing gas that causes the excessively increased internal pressure. The venting disk (126) is not restored to its original state when it ruptures due to a thermal event occurring within the secondary battery (100). The venting disk (126) may be any venting disk known in the art and is not particularly limited.

[0058] In some embodiments, the first MTB (120a) may further include a check valve (128). The check valve (128) may be configured to open to discharge internal gas when the internal pressure of the secondary battery (100) becomes higher than a predetermined pressure, and to close again when the internal pressure is relieved by the discharge of the gas. Since the check valve (128) does not have a part that is ruptured by the discharge of the gas, it can be restored to its original state after the discharge of the internal gas.

[0059] In some embodiments, the first MTB (120a) may further include an electrolyte injection port (127) capable of injecting an electrolyte. In some embodiments, the electrolyte injection port (127) may be provided in only one of the first MTB (120a) and the second MTB (120b).

[0060] The electrolyte injected through the electrolyte injection port (127) may be an electrolyte used for a typical lithium secondary battery, and is not particularly limited.

[0061] A bus bar may be further provided within the above first MTB (120a). Fig. 3 is a schematic diagram showing a cross-section of the first MTB (120a) cut along a plane passing through the electrode terminal portion (124) and perpendicular to a third direction (e.g., the Z-axis direction).

[0062] Referring to FIG. 3, the bus bar (125) may be provided to make surface contact with the electrode terminal portion (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 including one or more of these.

[0063] The bus bar (125) may be configured to make surface contact with the electrode lead (116) of the stacked electrode assembly (110). In some embodiments, the bus bar (125) may be joined to the electrode lead (116) by welding. In some embodiments, the bus bar (125) may be joined to the electrode lead (116) by a fastener, for example, by a rivet.

[0064] In some embodiments, the bus bar (125) may include a center portion (125c) having a planar shape extending horizontally in the first direction (e.g., X-axis direction) and an edge portion (125e) extending by bending from the center portion (125c). The center portion (125c) may be configured to form a generally U-shaped cross-sectional shape together with the edge portion (125e) and may extend in the third direction (e.g., Z-axis direction). In some embodiments, the edge portion (125e) may have a plane extending perpendicularly to the first direction (e.g., X-axis direction).

[0065] The above bus bar (125) can make surface contact with the electrode terminal portion (124) at the center portion (125c). The above bus bar (125) can make surface contact with the electrode lead (116) at the edge portion (125e).

[0066] 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 being concentrated at a specific portion of the electrode lead (116) due to an external force applied to the stacked electrode assembly (110), thereby improving safety.

[0067] Since the secondary battery (100) of the present invention accommodates all units having respective functions within the MTB (120a, 120b), such as an electrode terminal portion (124), a bus bar (125), a venting disk (126), a check valve (128), and an electrolyte injection port (127), the battery cell itself has a function equivalent to a conventional battery module. Therefore, the secondary battery (100) of the present invention can have a high degree of freedom and compatibility, and is advantageous for implementing cell-to-pack.

[0068]

[0069] Fig. 4 is a partially exploded perspective view showing a method of joining a laminate sheet (130) of a secondary battery (100) according to one embodiment of the present invention. Fig. 5 is a partial cross-sectional view of a laminate sheet (130) according to one embodiment of the present invention.

[0070] Referring to FIGS. 4 and 5, the laminate sheet (130) may be configured to wrap around a side surface of the stacked electrode assembly (110). In some embodiments, the laminate sheet (130) may be attached to a side surface of the MTB (120a, 120b) so as to at least partially cover the side surface of the MTB (120a, 120b). In some embodiments, the laminate sheet (130) may cover all of the side surfaces of the MTB (120a, 120b) that are parallel to the second direction (e.g., the Y-axis direction). In other embodiments, the laminate sheet (130) may cover only a portion of the side surfaces of the MTB (120a, 120b) that are parallel to the second direction (e.g., the Y-axis direction).

[0071] The above laminate sheet (130) may include a flexible metal layer (134), an inner resin layer (132) provided on one side of the metal layer (134), and an outer resin layer (136) provided on the other side of the metal layer (134).

[0072] The metal layer (134) can maintain an appropriate thickness and prevent water vapor, oxygen, and other gases from penetrating from the outside to the inside, and can prevent electrolyte leakage. In some embodiments, the metal layer (134) may include at least one selected from iron (Fe), carbon (C), chromium (Cr), manganese (Mn), nickel (Ni), aluminum (Al), and alloys thereof, but is not limited thereto. When the metal layer (134) is made of a material containing iron, the mechanical strength is strengthened, and when it is made of an aluminum material, the flexibility is improved, and thus, aluminum metal foil is mainly used.

[0073] The above metal layer (134) can be relatively easily deformed by a force applied from the outside, and can be configured to have an appropriate thickness and mechanical strength so that cracks or holes do not occur even when repeatedly deformed.

[0074] In some embodiments, the metal layer (134) can have a thickness of about 20 micrometers (μm) to about 100 μm. In some embodiments, the thickness of the metal layer (134) can have a range of about 20 μm to about 100 μm, about 25 μm to about 95 μm, about 30 μm to about 90 μm, about 35 μm to about 85 μm, about 40 μm to about 80 μm, about 45 μm to about 75 μm, about 50 μm to about 70 μm, about 55 μm to about 60 μm, or any two of these values.

[0075] The internal resin layer (132) provided on one side of the metal layer (134) may include a heat-sealing layer. In some embodiments, the internal resin layer (132) may include a polyolefin-based material capable of performing a sealing function through fusion. In some embodiments, the internal resin layer (132) may include a modified propylene such as cast polypropylene (CPP), or a polypropylene-butylene-ethylene terpolymer.

[0076] The above inner resin layer (132) can be formed by coating or laminating one side of the above metal layer (134).

[0077] The external resin layer (136) provided on the other side of the metal layer (134) can act as a base substrate and a protective layer for forming the laminate sheet (130). The external resin layer (136) can include an insulating material such as polyethylene terephthalate (PET) or nylon.

[0078] In some embodiments, the inner resin layer (132) and the outer resin layer (136) may each have a thickness of about 10 micrometers (μm) to about 50 μm. In some embodiments, the thickness of each of the inner resin layer (132) and the outer resin layer (136) may have a thickness of about 10 μm to about 50 μm, about 12 μm to about 48 μm, about 15 μm to about 45 μm, about 17 μm to about 43 μm, about 20 μm to about 40 μm, about 22 μm to about 38 μm, about 25 μm to about 35 μm, about 27 μm to about 33 μm, or a range between any two of these values.

[0079] In some embodiments, an adhesive resin layer may be further provided between the inner resin layer (132) and the metal layer (134) and / or between the outer resin layer (136) and the metal layer (134). The adhesive resin layer may be provided for smooth adhesion between different materials. The adhesive resin layer may be formed as a single layer or multiple layers. In some embodiments, the adhesive resin layer may include a polyolefin-based resin, a polyurethane-based resin, an epoxy-based resin, or a mixture thereof.

[0080] In some embodiments, the inner resin layer (132) may be fused to the side surfaces of the MTBs (120a, 120b) at both ends in the second direction (e.g., Y-axis direction). The stacked electrode assembly (110) may be encapsulated within the secondary battery by the inner resin layer (132) surrounding and fused to the side surfaces of the MTBs (120a, 120b). The inner resin layer (132) may be melted by heating while in contact with the side surfaces of the MTBs (120a, 120b) and then cooled to be fused onto the side surfaces.

[0081] The above laminate sheet (130) can be placed so that the inner resin layers (132) face each other at the joint (130m) after surrounding the side surfaces of the MTBs (120a, 120b) and the stacked electrode assembly (110), and then the inner resin layers (132) facing each other can be fused together.

[0082] The above-mentioned joining part (130m) may be positioned on any one side of the stacked electrode assembly (110). In some embodiments, the joining part (130m) may surround the stacked electrode assembly (110) and be positioned in a third direction (e.g., the Z-axis direction) of the stacked electrode assembly (110).

[0083] As described above, in the secondary battery (100) of the present invention, since the stacked electrode assembly (110) is directly surrounded by the laminate sheet (130) without a forming process for the laminate sheet (130), unit cells can be accommodated with a thickness greater than that defined in the conventional forming process. Therefore, the secondary battery (100) of the present invention is advantageous in implementing a large-capacity cell.

[0084]

[0085] (Example 2)

[0086] Fig. 6a is a perspective view showing the main part of a secondary battery (100a) according to another embodiment of the present invention. Fig. 6b is a partial perspective view showing an enlarged portion of a part of the secondary battery (100a) of Fig. 6a. Fig. 7 is a side view of a secondary battery (100a) according to another embodiment of the present invention.

[0087] The above secondary battery (100a) differs from the embodiment described with reference to FIGS. 1a to 4 in that the MTB is provided only on one side of the stacked electrode assembly extending in the second direction (e.g., the Y-axis direction). Therefore, the following description will focus on these differences, and additional description of overlapping parts will be omitted.

[0088] Referring to FIGS. 6A to 7, since the MTB (120c) is provided only on one side of the stacked electrode assembly, not on both sides, both electrodes of the stacked electrode assembly are connected to the MTB (120c). That is, the MTB (120c) is provided only on one side of the stacked electrode assembly in the second direction (e.g., Y-axis direction), and the joint portion (130m) can be extended without the MTB on the other side of the stacked electrode assembly in the second direction (e.g., Y-axis direction).

[0089] Since the MTB is provided on only one side of the stacked electrode assembly, the MTB (120c) is provided with a first electrode terminal portion (124a) and a second electrode terminal portion (124b) of different polarities. One of the first electrode terminal portion (124a) and the second electrode terminal portion (124b) may be a terminal portion corresponding to the cathode, and the other may be a terminal portion corresponding to the anode.

[0090] In FIG. 6b, a venting disk (126) is shown as being provided between the first electrode terminal portion (124a) and the second electrode terminal portion (124b), but the relative positions of the first electrode terminal portion (124a), the second electrode terminal portion (124b), and the venting disk (126) within the MTB (120c) are not particularly limited.

[0091] The laminated portion (130m) of the laminated sheet (130) can extend in a second direction (e.g., the Y-axis direction) from one side (the upper side in FIG. 7) in the third direction (e.g., the Z-axis direction) of the stacked electrode assembly. Furthermore, the laminated portion (130m) can extend in the third direction (e.g., the Z-axis direction) from the other side. In FIG. 7, the stacked electrode assembly is surrounded by the laminated sheet (130).

[0092] While the embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the appended claims. Therefore, modifications to future embodiments of the present invention will not depart from the scope of the invention.

Claims

1. A stacked electrode assembly in which a plurality of unit cells are stacked in a first direction and have electrode leads at both ends in a second direction perpendicular to the first direction; A multifunctional terminal block (MTB) provided at both ends of the stacked electrode assembly; and A laminate sheet covering the side of the stacked electrode assembly; Includes, The above MTB is, An electrode terminal electrically connected to the electrode lead of the stacked electrode assembly; and A venting disk that ruptures when internal pressure increases to release gas. A secondary battery containing:

2. In paragraph 1, The above MTB further includes a check valve, A secondary battery characterized in that the check valve is configured to open to discharge internal gas when the internal pressure of the secondary battery is higher than a certain pressure, and to close again after the internal pressure is relieved.

3. In paragraph 1, A secondary battery characterized in that the laminate sheet at least partially covers a side surface of the MTB.

4. In paragraph 3, A secondary battery characterized in that the laminate sheet is fused to the side of the MTB.

5. In paragraph 1, A secondary battery characterized in that the above MTB further includes an electrolyte injection port configured to inject an electrolyte.

6. In paragraph 1, A secondary battery characterized in that the laminate sheet is configured to surround the side surface of the stacked electrode assembly and then be fused to one side of the stacked electrode assembly so as to surround the side surface of the stacked electrode assembly.

7. In paragraph 6, The above laminate sheet: A metal layer having flexibility; An internal resin layer provided on one side of the metal layer; and An outer resin layer provided on the other side of the metal layer; Including, A secondary battery characterized in that the laminate sheet wraps the side of the stacked electrode assembly by fusing the inner resin layers together.

8. In paragraph 7, A secondary battery characterized in that the inner resin layer comprises casted polypropylene (CPP).

9. In paragraph 7, A secondary battery characterized in that the inner resin layer is fused to the side of the MTB.

10. In paragraph 1, A secondary battery characterized in that the above MTB further includes a bus bar electrically connecting the electrode lead of the stacked electrode assembly and the electrode terminal portion.

11. A stacked electrode assembly in which a plurality of unit cells are stacked in a first direction, extend in a second direction perpendicular to the first direction, and have electrode leads at their ends; a multifunctional terminal block (MTB) coupled to the electrode leads of the stacked electrode assembly; and A laminate sheet wrapping the stacked electrode assembly together with the MTB; Includes, The above MTB is, An electrode terminal electrically connected to the electrode lead of the stacked electrode assembly; and A bus bar electrically connecting the electrode lead and the electrode terminal; A secondary battery containing:

12. In paragraph 11, The above MTB further includes an MTB housing that accommodates the electrode terminal portion and the bus bar, A secondary battery characterized in that the electrode terminal portion is exposed to the outside through a through hole provided in the MTB housing.

13. In paragraph 12, A secondary battery characterized in that the stacked electrode assembly extends in a second direction perpendicular to the first direction, and the through hole is provided at an end of the MTB housing toward the second direction.

14. In paragraph 12, The laminate sheet surrounds the side of the stacked electrode assembly and has a bonding portion in the third direction of the stacked electrode assembly, A secondary battery characterized in that the laminate sheet at least partially covers a side surface of the MTB.

15. In paragraph 11, The above busbar: A center portion having a planar shape configured to make surface contact with the electrode terminal portion and extending horizontally in the first direction; and An edge portion extending and bending from the center portion; A secondary battery characterized by including:

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