Secondary batteries

Abstract

A secondary battery is provided comprising: a stacked electrode assembly in which multiple unit batteries are stacked in a first direction and electrode leads are provided 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 sides of the stacked electrode assembly, wherein the MTB includes electrode terminal portions electrically connected to the electrode leads of the stacked electrode assembly, and a rupture disk that bursts to release gas when internal pressure increases.

Description

Technical Field

[0001] The present invention relates to a secondary battery, and more specifically, to a secondary battery that is not only advantageous for implementing a large-capacity cell, but also advantageous for constructing a battery pack with high degrees of freedom and compatibility, and has improved safety.

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0075259 filed on June 13, 2023, and all the contents disclosed in the literature of the Korean patent application are included as part of this specification.

Background Art

[0003] Unlike a primary battery, a secondary battery can be charged and discharged multiple times. Secondary batteries are widely used as an energy source for various wireless devices such as handsets, notebook computers, and wireless vacuum cleaners. In recent years, due to improvements in energy density and economies of scale, the manufacturing cost per unit capacity of secondary batteries has decreased dramatically, and as the cruising range of battery electric vehicles (BEVs) has increased to a level comparable to that of fuel vehicles, the main use of secondary batteries has shifted from mobile devices to mobility.

[0004] On the other hand, in recent years, the demand for large-capacity battery packs applied to electric vehicles and the like has been increasing. The large-capacity battery packs installed in automobiles are required to enhance safety along with increasing their capacity.

Summary of the Invention

Problems to be Solved by the Invention

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

Means for Solving the Problems

[0006] To achieve the above technical objectives, the present invention provides a secondary battery comprising: a stacked electrode assembly in which a plurality of unit batteries are stacked in a first direction and electrode leads are provided 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 sides 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 rupture disk that bursts to release gas when the internal pressure increases.

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

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

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

[0010] In some embodiments, the MTB may further include an electrolyte inlet configured for the injection of an electrolyte.

[0011] In some embodiments, the laminate sheet can enclose the sides of the stacked electrode assembly by fusing it with the other sheet on one side of the stacked electrode assembly.

[0012] In some embodiments, the laminate sheet includes a flexible metal layer, an internal resin layer provided on one side of the metal layer, and an external resin layer provided on the other side of the metal layer, and the internal resin layers are fused together so that the laminate sheet wraps around the side of the stacked electrode assembly.

[0013] In some embodiments, the internal resin layer may include unoriented cast polypropylene (CPP).

[0014] In some embodiments, the internal resin layer can be fused to the side surface of the MTB.

[0015] In some embodiments, the MTB may further include a busbar that electrically connects the electrode leads and electrode terminals of the stacked electrode assembly.

[0016] Another aspect of the present invention provides a secondary battery comprising: a stacked electrode assembly in which a plurality of unit batteries are stacked in a first direction and extending in a second direction perpendicular to the first direction, with electrode leads at its ends; a multifunctional terminal block (MTB) coupled to the electrode leads of the stacked electrode assembly; and a laminate sheet enclosing 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 busbar 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 busbar, and the electrode terminal portion may be exposed to the outside through a through hole provided in the MTB housing.

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

[0019] In some embodiments, after surrounding the side surface of the stacked electrode assembly, the laminate sheet has a joint portion joined in the third direction of the stacked electrode assembly, and the laminate sheet may at least partially cover the side surface of the MTB.

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

Advantages of the Invention

[0021] The secondary battery according to an embodiment of the present invention is not only advantageous for implementing a large-capacity cell, but also advantageous for configuring a battery pack with high degrees of freedom and compatibility, and may have improved safety.

[0022] The effects obtainable 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 having ordinary knowledge in the technical field to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects associated with implementing the exemplary embodiments of the present disclosure can also be derived by those having ordinary knowledge in the technical field from the exemplary embodiments of the present disclosure.

Brief Description of the Drawings

[0023] [Figure 1a] It is a perspective view showing a main part of a secondary battery according to an embodiment of the present invention. [Figure 1b] It is a partial perspective view showing an enlarged part of the secondary battery of FIG. 1a. [Figure 2] It is a schematic perspective view showing a state where the laminate sheet is removed from the secondary battery of FIG. 1. [Figure 3] It is a schematic view showing a cross section obtained by cutting the first MTB in a plane perpendicular to the third direction through the electrode terminal portion. [Figure 4]It is a partially exploded perspective view showing a bonding method of a laminate sheet of a secondary battery according to an embodiment of the present invention. [Figure 5] It is a partial cross-sectional view of a laminate sheet according to an embodiment of the present invention. [Figure 6a] It is a perspective view showing a main part of a secondary battery according to an embodiment of the present invention. [Figure 6b] It is a partial perspective view showing an enlarged part of the secondary battery of FIG. 6a. [Figure 7] It is a side view of a secondary battery according to another embodiment of the present invention as seen from the side.

Mode for Carrying Out the Invention

[0024] Hereinafter, preferred embodiments of the concept of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments of the concept of the present invention can be deformed into various different forms, and the scope of the concept of the present invention should not be construed as being limited by the embodiments described above. The embodiments of the concept of the present invention are preferably construed as being provided to more fully explain the concept of the present invention to those having average knowledge in the art. The same reference numerals mean the same elements throughout. Further, various elements and regions in the drawings are schematically drawn. Therefore, the concept of the present invention is not limited by the relative sizes or intervals depicted in the attached drawings.

[0025] Terms such as first, second, etc. can be used to describe various components, but the above components are not limited by the above terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the concept of the present invention, the first component can be named the second component, and conversely, the second component can be named the first component.

[0026] The terms used in this application are used solely to describe specific embodiments and are not intended to limit the concepts of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, expressions such as “includes” or “has” are intended to specify the existence of features, quantities, steps, operations, components, parts, or combinations thereof described in the specification, and are understood not to pre-exist to exclude the existence or possibility of adding one or more other features, quantities, steps, operations, components, parts, or combinations thereof.

[0027] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as those commonly understood by those of ordinary skill in the art to which the concepts of this invention pertain. Furthermore, terms defined in commonly used dictionaries may be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an overly formal sense unless explicitly defined herein.

[0028] Where a particular embodiment can be otherwise realized, a specific sequence of steps may be performed in a different order than that described. For example, two steps described consecutively may be performed substantially simultaneously, or in the reverse order of the description.

[0029] In the accompanying drawings, deformations of shape, for example, due to manufacturing techniques and / or tolerances, may be expected. Therefore, embodiments of the present invention should not be construed as being limited to specific shapes of the regions shown herein, and may include, for example, changes in shape resulting from the manufacturing process. All terms used herein, "and / or," include each of the components mentioned and all combinations of one or more of them. Furthermore, the term "substrate" as used herein may mean the substrate itself or a laminated structure including a substrate and a predetermined layer or film formed on its surface. Also, "surface of the substrate" as used herein may mean the exposed surface of the substrate itself or an outer surface such as a predetermined layer or film formed on the substrate.

[0030] (First Embodiment) Figure 1a is a perspective view showing the main parts of a secondary battery 100 according to one embodiment of the present invention. Figure 1b is a partial perspective view showing an enlarged portion of the secondary battery 100 in Figure 1a. Figure 2 is a schematic perspective view showing the secondary battery 100 in Figure 1a with the laminate sheet 130 removed.

[0031] In the following drawings, the secondary battery 100 is shown defined in a vertical coordinate system defined as a first direction along the X-axis, a second direction along the Y-axis, and a third direction along the Z-axis, all of which are perpendicular to each other. However, the first, second, and third directions are not particularly limited and only need to be perpendicular to each other.

[0032] Referring to Figures 1a to 2, the secondary battery 100 includes a stacked electrode assembly 110, multifunctional terminal blocks (MTBs) 120a and 120b, and a laminate sheet 130.

[0033] The stacked electrode assembly 110 described above may include a plurality of unit cells 111 stacked in a first direction (e.g., the X-axis direction). Each of the unit cells 111 may have an electrode material coated on a metal foil that acts as a current collector.

[0034] Each unit cell 111 may have a thin, plate-like body extending in a second direction (for example, the Y-axis direction). Each unit cell 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 arranged in alternating stacks of one positive electrode unit cell and one negative electrode unit cell. The positive electrode unit cells and the negative electrode unit cells may be separated from each other by a separator membrane.

[0035] In some other embodiments, the plurality of unit cells 111 may consist of a plurality of positive electrode unit cells and a plurality of negative electrode unit cells stacked alternately. The plurality of positive electrode unit cells and the plurality of negative electrode unit cells may be separated from each other by a separator membrane.

[0036] The stacked electrode assembly 110 may have electrode leads 116 at both ends in the second direction (for example, the Y-axis direction). The electrode leads 116 may be electrically connected to electrode tabs of the plurality of unit batteries 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.

[0037] 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 batteries 111 included in the stacked electrode assembly 110 may be coupled to a first electrode lead on one side and to a second electrode lead on the other side. The remaining half of the plurality of unit batteries 111 included in the stacked electrode assembly 110 may be coupled to a third electrode lead on one side and to a fourth electrode lead on the other side. However, the present invention is not limited thereto.

[0038] 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.

[0039] A first MTB 120a may be provided at one end of the stacked electrode assembly 110 in the second direction (e.g., the 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 a different polarity. The first MTB 120a will be described below, from which the configuration of the second MTB 120b can be understood by an ordinary technician.

[0040] The first MTB120a described above may include an MTB housing 122, an electrode terminal portion 124 housed within the MTB housing 122, and a busbar 125 (see Figure 3) that electrically connects the electrode terminal portion 124 and the electrode lead 116.

[0041] The MTB housing 122 described above 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.

[0042] The MTB housing 122 may include a through hole 122h that exposes the electrode terminal portion 124, which will be described later. The through hole 122h may be provided in the MTB housing 122 such that the electrode terminal portion 124 is exposed in the second direction (for example, the Y-axis direction). Therefore, the through hole 122h may be provided on a plane of the MTB housing 122 perpendicular to the second direction (for example, the Y-axis direction). The through hole 122h may also 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 edge shape of the portion of the electrode terminal portion 124 that is exposed to the outside.

[0043] A typical engineer can understand that the first MTB120a described above may further include, as needed, through-holes for venting discs, through-holes for check valves, through-holes for electrolyte injection ports, and so on.

[0044] The electrode terminal portion 124 is housed 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 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.

[0045] In some embodiments, the exposed surface of the electrode terminal portion 124 that is exposed to the outside from the MTB housing 122 may be a plane. In some embodiments, the exposed surface may have a plane that extends perpendicular to the second direction (for example, the Y-axis direction).

[0046] 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.

[0047] In some embodiments, the first MTB 120a may include a rupture disk 126 configured to release gases causing an excessive increase in internal pressure in the secondary battery 100 by rupturing when the internal pressure of the secondary battery 100 increases excessively. Once the venture disk 126 ruptures due to a thermal event occurring inside the secondary battery 100, it does not return to its original state. The venture disk 126 can be any venture disk known in the art and is not particularly limited.

[0048] In some embodiments, the first MTB 120a may further include a check valve 128. The check valve 128 may be configured to open to release internal gas when the internal pressure of the secondary battery 100 rises above a predetermined pressure, and to close again when the internal pressure is relieved by the release of the gas. Since there is no part that would burst upon the release of the gas, the check valve 128 can be restored to its original state after the internal gas has been released.

[0049] In some embodiments, the first MTB120a may further include an electrolyte inlet 127 into which an electrolyte can be injected. In some embodiments, the electrolyte inlet 127 may be provided in only one of the first MTB120a and the second MTB120b.

[0050] The electrolyte injected through the electrolyte inlet 127 can be any electrolyte used for a typical lithium secondary battery, and is not particularly limited.

[0051] Busbars may be further provided within the first MTB120a. Figure 3 is a schematic diagram showing a cross-section of the first MTB120a cut through the electrode terminal portion 124 in a plane perpendicular to the third direction (for example, the Z-axis direction).

[0052] Referring to Figure 3, the busbar 125 may be provided to make surface contact with the electrode terminal portion 124. The busbar 125 may be made of a metallic material with low electrical resistance. In some embodiments, the busbar 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.

[0053] The busbar 125 may be configured to make surface contact with the electrode lead 116 of the stacked electrode assembly 110. In some embodiments, the busbar 125 may be joined to the electrode lead 116 by welding. In some embodiments, the busbar 125 may be joined to the electrode lead 116 by fasteners, for example by rivets.

[0054] In some embodiments, the busbar 125 may include a planar center portion 125c extending horizontally in the first direction (e.g., the X-axis direction) and an edge portion 125e extending bent from the center portion 125c. The center portion 125c may be configured to have a substantially U-shaped cross-section together with the edge portion 125e and may extend in the third direction (e.g., the Z-axis direction). In some embodiments, the edge portion 125e may have a plane extending perpendicularly to the first direction (e.g., the X-axis direction).

[0055] The busbar 125 can make surface contact with the electrode terminal portion 124 at its center portion 125c. The busbar 125 can make surface contact with the electrode lead 116 at its edge portion 125e.

[0056] In some embodiments, the electrode lead 116 may include a pre-bended portion that is bent in a portion that does not come into contact with the busbar 125. This pre-bended portion can prevent stress from concentrating on a specific part of the electrode lead 116 due to external forces applied to the stacked electrode assembly 110, thereby potentially improving safety.

[0057] The secondary battery 100 of the present invention houses all the units having their respective functions within the MTB 120a and 120b, such as the electrode terminal section 124, busbar 125, venting disk 126, check valve 128, and electrolyte inlet 127. Therefore, the battery cell itself has functions equivalent to those of a conventional battery module. Accordingly, the secondary battery 100 of the present invention can have a high degree of flexibility and compatibility, and is advantageous for realizing cell-to-pack.

[0058] Figure 4 is a partially exploded perspective view showing the bonding method of the laminate sheet 130 of the secondary battery 100 according to one embodiment of the present invention. Figure 5 is a partially cross-sectional view of the laminate sheet 130 according to one embodiment of the present invention.

[0059] Referring to Figures 4 and 5, the laminate sheet 130 may be configured to wrap around the sides of the stacked electrode assembly 110. In some embodiments, the laminate sheet 130 may be attached to the sides of the MTBs 120a and 120b so as to at least partially cover the sides of the MTBs 120a and 120b. In some embodiments, the laminate sheet 130 may cover the entire sides of the MTBs 120a and 120b 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 sides of the MTBs 120a and 120b parallel to the second direction (e.g., the Y-axis direction).

[0060] The laminate sheet 130 may include a flexible metal layer 134, an internal resin layer 132 provided on one side of the metal layer 134, and an external resin layer 136 provided on the other side of the metal layer 134.

[0061] The metal layer 134 maintains an appropriate thickness, prevents water vapor, oxygen, and other gases from penetrating from the outside to the inside, and can prevent leakage of the electrolyte. In some embodiments, the metal layer 134 may, but is not limited to, contain one or more selected materials from iron (Fe), carbon (C), chromium (Cr), manganese (Mn), nickel (Ni), aluminum (Al), and alloys thereof. When the metal layer 134 is made of an iron-containing material, the mechanical strength is increased, and when it is made of an aluminum material, the flexibility is improved, so aluminum metal foil is usually mainly used.

[0062] The metal layer 134 described above can be configured to be relatively easily deformable by external forces and to have an appropriate thickness and mechanical strength such that cracks or holes do not occur even after repeated deformation.

[0063] In some embodiments, the metal layer 134 may have a thickness of about 20 micrometers (μm) to about 100 μm. In some embodiments, the thickness of the metal layer 134 may be in the 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.

[0064] The internal resin layer 132 provided on one side of the metal layer 134 may include a heat-bonding layer. In some embodiments, the internal resin layer 132 may include a polyolefin material capable of sealing by fusion. In some embodiments, the internal resin layer 132 may include modified propylene such as unoriented polypropylene (casted polypropylene: CPP), or a polypropylene-butylene-ethylene ternary copolymer.

[0065] The internal resin layer 132 may be formed by coating or laminating it to one side of the metal layer 134.

[0066] The external resin layer 136 provided on the other side of the metal layer 134 can act as a base substrate and protective layer for forming the laminate sheet 130. The external resin layer 136 may contain an insulating material such as polyethylene terephthalate (PET) or nylon.

[0067] In some embodiments, the internal resin layer 132 and the external resin layer 136 may each have a thickness of about 10 micrometers (μm) to about 50 μm. In some embodiments, the thickness of the internal resin layer 132 and the external resin layer 136 may be in the range 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 any two of these values.

[0068] In some embodiments, an adhesive resin layer may be further provided between the internal resin layer 132 and the metal layer 134, and / or between the external resin layer 136 and the metal layer 134. The adhesive resin layer may be provided for smooth adhesion between dissimilar 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 resin, a polyurethane resin, an epoxy resin, or a mixture thereof.

[0069] In some embodiments, the internal resin layer 132 can be fused to the sides of the MTBs 120a and 120b at both ends in a second direction (e.g., the Y-axis direction). The stacked electrode assembly 110 can be sealed inside the secondary battery by the internal resin layer 132 fusing around the sides of the MTBs 120a and 120b. The internal resin layer 132 can be fused onto the sides of the MTBs 120a and 120b by heating and melting in contact with the sides of the MTBs 120a and 120b, followed by cooling.

[0070] The laminate sheet 130 is placed around the sides of the MTB 120a and 120b and the stacked electrode assembly 110, and then the internal resin layers 132 are brought into close contact at the joint 130m so that they face each other, after which the opposing internal resin layers 132 can be fused together.

[0071] The joint portion 130m may be located on any one side of the stacked electrode assembly 110. In some embodiments, the joint portion 130m may be located in a third direction (e.g., the Z-axis direction) of the stacked electrode assembly 110 after surrounding it.

[0072] As described above, in the secondary battery 100 of the present invention, the laminate sheet 130 directly surrounds the stacked electrode assembly 110 without a forming process for the laminate sheet 130, so it is possible to accommodate unit batteries with a thickness greater than that defined by the conventional forming process. Therefore, the secondary battery 100 of the present invention is advantageous for realizing high-capacity cells.

[0073] (Second Embodiment) Figure 6a is a perspective view showing the main parts of a secondary battery 100a according to another embodiment of the present invention. Figure 6b is a partial perspective view showing an enlarged portion of the secondary battery 100a in Figure 6a. Figure 7 is a side view of the secondary battery 100a according to another embodiment of the present invention.

[0074] The secondary battery 100a described above differs from the embodiment described with reference to Figures 1a to 4 in that the MTB is provided only on one side of the stacked electrode assembly extending in a second direction (for example, the Y-axis direction). Therefore, the following description will focus on these differences, and any overlapping parts will be omitted.

[0075] Referring to Figures 6a to 7, the MTB 120c is provided on only one side of the stacked electrode assembly, rather than both sides, so that both electrodes of the stacked electrode assembly are connected to the MTB 120c. That is, the MTB 120c is provided on only one side of the stacked electrode assembly in the second direction (e.g., the Y-axis direction), and the joint 130m may extend on the other side of the stacked electrode assembly in the second direction (e.g., the Y-axis direction) without the MTB.

[0076] 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 having opposite polarities. One of the first electrode terminal portion 124a and the second electrode terminal portion 124b may be the terminal portion corresponding to the cathode, and the other may be the terminal portion corresponding to the anode.

[0077] In Figure 6b, a venting disk 126 is shown to be 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.

[0078] The joint portion 130m of the laminate sheet 130 may extend in a second direction (e.g., the Y-axis direction) from one side of the stacked electrode assembly in a third direction (e.g., the Z-axis direction) (the upper side in Figure 7). Furthermore, the joint portion 130m may extend in a third direction (e.g., the Z-axis direction) from the other side. In Figure 7, the stacked electrode assembly is surrounded by the laminate sheet 130.

[0079] As described above, embodiments of the present invention have been described in detail, but a person with ordinary skill in the art to which the present invention pertains can modify and implement the present invention in various ways without departing from the spirit and scope of the invention as defined in the appended claims. Therefore, future modifications of embodiments of the present invention will not depart from the art of the present invention. [Explanation of Symbols]

[0080] 100 Secondary battery 100A secondary battery 110 Stacked electrode assembly 110 Electrode assembly 111 Unit Battery 116 Electrode Leads 120a, 120b, 120c Multifunctional Terminal Block (MTB) 122 MTB Housing 122h through hole 124 Electrode terminal section 124a 1st electrode terminal part 124b 2nd electrode terminal section 125 Bus Bar 125c Center section 125e ​​Edge 126. Rupture disk 127 Electrolyte inlet 128 Check valve 130 Laminating Sheets 130m joint 132 Internal resin layer 134 Metal layer 136 Outer resin layer

Claims

1. A stacked electrode assembly comprising multiple unit batteries stacked in a first direction, with electrode leads at both ends in a second direction perpendicular to the first direction, A multi-functional terminal block (MTB) provided at both ends of the stacked electrode assembly, The assembly includes a laminate sheet that encloses the side surface of the stacked electrode assembly, The aforementioned MTB is, The electrode terminal portion electrically connected to the electrode lead of the stacked electrode assembly, A secondary battery comprising a venting disc that ruptures to release gas when internal pressure increases.

2. The aforementioned MTB further includes a check valve, The secondary battery according to claim 1, wherein the check valve is configured to open to release internal gas when the internal pressure of the secondary battery is higher than a certain pressure, and to close again after the internal pressure has been relieved.

3. The secondary battery according to claim 1, wherein the laminate sheet covers at least partially the side surface of the MTB.

4. The secondary battery according to claim 3, wherein the laminate sheet is fused to the side surface of the MTB.

5. The secondary battery according to claim 1, wherein the MTB further includes an electrolyte inlet configured for the injection of an electrolyte.

6. The secondary battery according to claim 1, wherein the laminate sheet surrounds the side surface of the stacked electrode assembly and then fuses with the laminate sheet on one side of the stacked electrode assembly to enclose the side surface of the stacked electrode assembly.

7. The aforementioned laminate sheet is A flexible metal layer, An internal resin layer provided on one side of the metal layer, The metal layer includes an external resin layer provided on the other side of the aforementioned metal layer, The secondary battery according to claim 6, wherein the laminate sheet wraps around the side surface of the stacked electrode assembly by fusing the internal resin layers together.

8. The secondary battery according to claim 7, wherein the internal resin layer includes unstretched polypropylene.

9. The secondary battery according to claim 7, wherein the internal resin layer is fused to the side surface of the MTB.

10. The secondary battery according to claim 1, wherein the MTB further includes a busbar that electrically connects the electrode leads and electrode terminals of the stacked electrode assembly.

11. A stack-type electrode assembly comprising multiple unit batteries stacked in a first direction, extending in a second direction perpendicular to the first direction, and having electrode leads at its ends, A multi-functional terminal block (MTB) coupled to the electrode leads of the stacked electrode assembly, The assembly includes a laminate sheet that encloses the stacked electrode assembly together with the MTB, The aforementioned MTB is, The electrode terminal portion electrically connected to the electrode lead of the stacked electrode assembly, A secondary battery comprising an electrode lead and a busbar that electrically connects the electrode terminal portion.

12. The MTB further includes an MTB housing that accommodates the electrode terminal portion and the busbar, The secondary battery according to claim 11, wherein the electrode terminal portion is exposed to the outside through a through hole provided in the MTB housing.

13. The secondary battery according to claim 12, wherein the stacked electrode assembly extends in a second direction perpendicular to the first direction, and the through-hole is provided at the end of the MTB housing toward the second direction.

14. The laminate sheet surrounds the side surface of the stacked electrode assembly and has a joint that is joined in a third direction of the stacked electrode assembly. The secondary battery according to claim 12, wherein the laminate sheet covers at least partially the side surface of the MTB.

15. The aforementioned busbar is A planar center portion is configured to make surface contact with the electrode terminal portion and extends horizontally in the first direction, The secondary battery according to claim 11, further comprising an edge portion that is bent and extends from the center portion.

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