Electrode assembly and secondary battery including the electrode assembly

Abstract

Disclosed are electrode assemblies and secondary batteries including the electrode assemblies. According to some embodiments, the electrode assembly may include a first electrode, a second electrode, and a separator between the first and second electrodes. The separator may include protrusions relative to the first and second electrodes, and a protective layer may be disposed on the protrusions.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2025-0018434, filed on February 13, 2025, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] The embodiments relate to an electrode assembly and a secondary battery including the electrode assembly. Background Technology

[0003] Unlike primary batteries, which are not designed for (re)charging, secondary (or rechargeable) batteries are designed to be discharged and recharged. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources for driving motors in hybrid and electric vehicles and for storing electricity (e.g., household and / or utility-scale power storage). A secondary battery typically includes an electrode assembly consisting of positive and negative electrodes, a housing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0004] The information disclosed in this section is provided only to enhance understanding of the context of the disclosure and therefore may contain information that does not form prior art. Summary of the Invention

[0005] Embodiments of this disclosure provide an electrode assembly and / or a secondary battery including the electrode assembly, which has improved safety.

[0006] An electrode assembly according to some embodiments may include a first electrode; a second electrode; and a diaphragm between the first electrode and the second electrode. The diaphragm may include protrusions relative to the first electrode and the second electrode, and a protective layer is disposed on the protrusions.

[0007] In some embodiments, the protective layer may be disposed on at least one of the top and bottom surfaces of the diaphragm.

[0008] In some embodiments, the protective layer may be spaced apart from the first electrode and the second electrode.

[0009] In some embodiments, the melting temperature of the protective layer may be 130°C to 900°C.

[0010] In some embodiments, the protective layer may include polyimide, polypropylene, or ionomer.

[0011] In some embodiments, the first electrode may include a first current collector and a first active material layer on the first current collector. The second electrode may include a second current collector and a second active material layer on the second current collector. The protective layer may include a first protective layer adjacent to the first active material layer and a second protective layer adjacent to the second active material layer.

[0012] In some embodiments, the thickness of the first protective layer may be greater than or equal to the thickness of the diaphragm and less than or equal to the thickness of the first active material layer, and the thickness of the second protective layer may be greater than or equal to the thickness of the diaphragm and less than or equal to the thickness of the second active material layer.

[0013] In some embodiments, the first protective layer may include a region having a thickness different from that of another region of the first protective layer, and / or the second protective layer may include a region having a thickness different from that of another region of the second protective layer.

[0014] In some embodiments, the protective layer may include a first-a protective layer and a second-a protective layer, wherein the second-a protective layer is closer to the first electrode or the second electrode than the first-a protective layer, and the width of the first-a protective layer is greater than the width of the second-a protective layer.

[0015] A secondary battery according to some embodiments may include a housing; an electrode assembly housed within the housing; electrode tabs connected to the electrode assembly; and leads connected to the electrode tabs. The electrode assembly may include: a first electrode; a second electrode; and a separator between the first electrode and the second electrode. The separator may include protrusions relative to the first electrode and the second electrode, with a protective layer disposed on the protrusions.

[0016] In some embodiments, the protrusion may include at least one of a first protrusion that overlaps with the electrode tab and a second protrusion that does not overlap with the electrode tab.

[0017] In some embodiments, the protective layer may be disposed on the first protrusion. The protective layer may be disposed on at least one of the top surface and the bottom surface of the diaphragm.

[0018] In some embodiments, the diaphragm may include an overlapping region that overlaps with the electrode tabs. The first electrode may include a first current collector and a first active material layer on the first current collector, the second electrode may include a second current collector and a second active material layer on the second current collector, the protective layer may include a first protective layer adjacent to the first active material layer and a second protective layer adjacent to the second active material layer, and the first protective layer may include a region having a thickness different from the thickness of another region of the first protective layer, and / or the second protective layer may include a region having a thickness different from the thickness of another region of the second protective layer.

[0019] In some embodiments, the electrode tabs may include a first electrode tab connected to the first electrode and a second electrode tab connected to the second electrode. The overlapping region may include a first overlapping region overlapping the first electrode tab and a second overlapping region overlapping the second electrode tab. The first protective layer may have a first-1 thickness at the first overlapping region and a first-2 thickness in the region excluding the first overlapping region, and the second protective layer may have a second-1 thickness at the second overlapping region and a second-2 thickness in the region excluding the second overlapping region. The first-1 thickness may be greater than the first-2 thickness, and the second-1 thickness may be greater than the second-2 thickness.

[0020] In some embodiments, the first electrode may be a positive electrode, the second electrode may be a negative electrode, and the thickness of the first protective layer may be greater than or equal to the thickness of the second protective layer.

[0021] In some embodiments, the second-first thickness may be greater than the first-first thickness.

[0022] In some embodiments, the first-1 thickness may be greater than the second-1 thickness.

[0023] In some embodiments, the first protective layer may further have a first-third thickness at the second overlapping region, the second protective layer may further have a second-third thickness at the first overlapping region, and the sum of the first-third thickness and the second-third thickness may be greater than the sum of the first-third thickness and the second-third thickness.

[0024] In some embodiments, the electrode tabs may include a first electrode tab connected to the first electrode and a second electrode tab connected to the second electrode. The first electrode may be a positive electrode, and the second electrode may be a negative electrode. The first electrode tab and the second electrode tab extend in opposite directions. The protrusions may include a first-1 protrusion overlapping the first electrode tab and a first-2 protrusion overlapping the second electrode tab. The protective layer may include a first-1 protective layer on the first-1 protrusion and a first-2 protective layer on the first-2 protrusion. The thickness of the first-1 protective layer may be greater than the thickness of the first-2 protective layer.

[0025] In some embodiments, the protective layer may include a first-b protective layer on the first protrusion and a second-b protective layer on the second protrusion, the first-b protective layer and the second-b protective layer extending in different directions. Attached Figure Description

[0026] The accompanying drawings, incorporated herein by reference, illustrate preferred embodiments and serve to further illustrate the technical ideas of this disclosure in conjunction with the detailed description of the following exemplary embodiments. This disclosure is not to be construed as being limited to the content shown in these drawings. In the drawings:

[0027] Figure 1 A perspective view of a secondary battery according to some embodiments of the present disclosure;

[0028] Figure 2 A side view of an electrode assembly according to some embodiments of the present disclosure;

[0029] Figure 3 A top view of an electrode assembly according to some embodiments of the present disclosure;

[0030] Figures 4-8 According to some embodiments of this disclosure Figure 3 A cross-sectional view taken from line A-A';

[0031] Figure 9 According to some embodiments of this disclosure Figure 3 A cross-sectional view taken from line B-B';

[0032] Figures 10-14 A top view of an electrode assembly according to some embodiments of the present disclosure;

[0033] Figure 15 This illustration shows an electrode assembly according to some embodiments of the present disclosure applied to another type of secondary battery;

[0034] Figure 16A perspective view of a battery module including a secondary battery according to some embodiments of the present disclosure;

[0035] Figure 17 and Figure 18 A perspective view of a battery pack including a battery module according to some embodiments of the present disclosure;

[0036] Figure 19 A perspective view of a vehicle including a battery pack according to some embodiments of the present disclosure; and

[0037] Figure 20 A side view of a vehicle including a battery pack according to some embodiments of the present disclosure. Detailed Implementation

[0038] The embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The terms or words used in this specification and claims should not be construed as having a conventional or dictionary meaning, but should be interpreted as meanings and concepts consistent with the technical spirit of this disclosure, based on the principle that the inventor is capable of being his / her own lexicographer to appropriately define the terms and concepts in order to best describe his / her invention.

[0039] The embodiments described in this specification and the configurations shown in the figures are merely some embodiments of this disclosure and do not represent all the technical spirit, aspects, and features of this disclosure. Accordingly, it should be understood that various equivalents and modifications that can replace or modify the embodiments described herein may exist at the time of filing this application.

[0040] It will be understood that when an element or layer is referred to as being "on" another element or layer, "connected to," or "linked to" another element or layer, it can be directly on, connected to, or linked to the other element or layer, or one or more intermediary elements or layers may be present. When an element or layer is referred to as being "directly on" another element or layer, "directly connected to," or "directly linked to" another element or layer, no intermediary element or layer is present. For example, when a first element is described as being "linked" or "connected" to a second element, the first element can be directly linked to or connected to the second element, or the first element can be indirectly linked to or connected to the second element via one or more intermediary elements.

[0041] In the figures, for clarity of illustration, the dimensions of various elements, layers, etc., may be enlarged. The same reference numerals indicate the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Furthermore, when describing embodiments of this disclosure, the use of "may" refers to "one or more embodiments of this disclosure." Expressions such as "at least one of" and "any one of" modify the entire column of elements, not individual elements of the column, when following a column of elements. When phrases such as "at least one of A, B, and C," "at least one of A, B, or C," "at least one selected from the group of A, B, and C," or "at least one selected from A, B, and C" are used to specify a column of elements A, B, and C, the phrase may refer to any and all suitable combinations or subsets of A, B, and C, such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the term "use" may be considered synonymous with the term "utilize." As used herein, the terms “substantially,” “about,” and similar terms are used as approximate terms rather than as terms of degree, and are intended to take into account the inherent variations in measured or calculated values ​​that would be recognized by one of ordinary skill in the art.

[0042] It will be understood that while the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or segment from another element, component, region, layer, or segment. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment.

[0043] For ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” and “above” may be used herein to describe the relationship between one element or feature illustrated in the figures and another element or feature. It will be understood that spatial relative terms are intended to encompass different orientations of the device in use or operation, other than those depicted in the figures. For example, if the device in the figures is flipped, an element described as “below” or “under” other elements or features would then be oriented as “above” or “above” other elements or features. Therefore, the term “below” can encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used herein should be interpreted accordingly.

[0044] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit this disclosure. As used herein, unless the context clearly indicates otherwise, the singular form “a” is also intended to include the plural form. It will be further understood that the terms “comprising” and / or “including” as used in this specification specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0045] Furthermore, any numerical ranges disclosed and / or enumerated herein are intended to include all subranges with the same numerical precision contained within the enumerated ranges. For example, the range “1.0 to 10.0” is intended to include all subranges between (and including) the enumerated minimum value of 1.0 and the enumerated maximum value of 10.0, i.e., a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit enumerated herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit enumerated herein is intended to include all higher numerical limits contained therein. Accordingly, the applicant reserves the right to amend this specification, including the claims, to expressly enumerate any subranges contained within the scope expressly enumerated herein.

[0046] Referring to two compared elements, features, etc., as “identical” can mean that they are “substantially the same.” Therefore, the phrase “substantially the same” can include cases with a deviation considered low in the art, such as 5% or less. Furthermore, when a parameter is said to be consistent in a given region, this can mean that it is consistent in terms of average value.

[0047] Throughout this specification, unless otherwise stated, each element may be a single element or a plurality of elements.

[0048] Placing any element "above (or below)" or "on (below)" another element means that the element can be positioned to contact the upper (or lower) surface of the element, and the other element can be positioned between the element and any element positioned on (or below) the element.

[0049] Additionally, it will be understood that when a component is referred to as a “link,” “connect,” or “attached” to another component, these components may be directly “connected,” “linked,” or “attached” to each other, or another component may be “between” these components.

[0050] Throughout this specification, unless otherwise stated, the phrase "A and / or B" means A, B, or A and B. That is, "and / or" includes any or all combinations of the listed items. Unless otherwise stated, the phrase "C to D" means C and above and D and below.

[0051] The electrode assembly and secondary battery according to embodiments will be described below with reference to the accompanying drawings.

[0052] Figure 1 This is a perspective view of a secondary battery according to some embodiments of the present disclosure.

[0053] refer to Figure 1 The secondary battery 1000 according to the embodiment may include a housing 100 and an electrode assembly 200.

[0054] The housing 100 may include an outer shell portion 110 and a cover portion 120. The outer shell portion 110 and the cover portion 120 may be connected. The housing 100 may be formed in the shape of a bag.

[0055] The housing portion 110 may include a recess 111 and a first sealing region 112. The housing portion 110 may include a receiving space. The housing portion 110 may include an inner bottom surface and an inner side surface formed by the recess 111. The receiving space may be formed by the inner bottom surface and the inner side surface.

[0056] The first sealing region 112 may be disposed at the edge of the outer casing portion 110. A sealing layer may be disposed on the first sealing region 112.

[0057] The cover 120 may include a cover portion 121 and a second sealing region 122.

[0058] The cover 121 can cover the housing 110. The cover 121 can cover the electrode assembly 200 housed in the housing 110.

[0059] The second sealing region 122 may be disposed at the edge of the cover portion 120. A sealing layer may be disposed on the second sealing region 122. The first sealing region 112 and the second sealing region 122 may overlap each other. When the outer casing portion 110 is covered by the cover portion 120, the first sealing region 112 and the second sealing region 122 may face each other. Therefore, the outer casing portion 110 and the cover portion 120 may be connected by the sealing layer.

[0060] The electrode assembly 200 can be housed within the housing 100. The electrode assembly 200 can be housed within the housing space of the housing 100. The electrode assembly 200 can be housed together with the electrolyte within the housing space.

[0061] exist Figure 1 In this embodiment, the electrode assembly is illustrated as being housed within a housing. However, the embodiment is not limited to this. Two or more electrode assemblies may be housed within the housing.

[0062] Electrode assembly 200 may include a first electrode 210, a second electrode 220, and a diaphragm 230. Electrode assembly 200 may be formed by stacking the first electrode 210, the second electrode 220, and the diaphragm 230. Electrode assembly 200 may be a Z-stacked electrode assembly, wherein the first electrode 210 and the second electrode 220 are inserted on both sides of the diaphragm 230 folded into a Z-stack.

[0063] The first electrode 210 may include a first current collector and a first active material layer on the first current collector. The first current collector may include a metal foil such as aluminum or an aluminum alloy. The first active material layer may include a transition metal oxide. Further, the first electrode 210 may be a positive electrode.

[0064] The first electrode 210 can be connected to the first electrode contact 310. In some embodiments, the first active material layer is not disposed on the first electrode contact 310. The first electrode contact 310 can be soldered to a first current collector on which the first active material layer is not disposed. In some embodiments, the first electrode contact 310 can be integrally formed with the first current collector. Further, the first current collector may include a first uncoated portion on which the first active material layer is not disposed. The first uncoated portion may be the first electrode contact 310. The first electrode contact 310 may include the same material as the first current collector. In some embodiments, the first electrode contact 310 may be a substrate contact.

[0065] The second electrode 220 may include a second current collector and a second active material layer on the second current collector. The second current collector may include a metal foil such as copper, a copper alloy, nickel, or a nickel alloy. The second active material layer may include graphite or carbon. Further, the second electrode 220 may be a negative electrode.

[0066] The second electrode 220 can be connected to the second electrode contact 320. The second active material layer is not disposed on the second electrode contact 320. The second electrode contact 320 can be soldered to a second current collector on which the second active material layer is not disposed. The second electrode contact 320 can be integrally formed with the second current collector. Further, the second current collector may include a second uncoated portion on which the second active material layer is not disposed. The second uncoated portion may be the second electrode contact 320. The second electrode contact 320 may include the same material as the second current collector. In some embodiments, the second electrode contact 320 may be a substrate contact.

[0067] The first electrode tab 310 and the second electrode tab 320 can each be connected to a lead. The first electrode tab 310 can be connected to a first lead 410. The first electrode tab 310 can be connected to a first external terminal via the first lead 410. The second electrode tab 320 can be connected to a second lead 420. The second electrode tab 320 can be connected to a second external terminal via the second lead 420. The first lead 410 and the first electrode tab 310 can be made of the same material. The second lead 420 and the second electrode tab 320 can be made of the same material. The electrode tabs 310, 320 and the leads 410, 420 can be connected by welding or adhesive components.

[0068] An insulating layer may be disposed on the lead wire. A first insulating layer 510 may be disposed on the first lead wire 410. The first insulating layer 510 may be configured to surround a portion of the first lead wire 410. A second insulating layer 520 may be disposed on the second lead wire 420. The second insulating layer 520 may be configured to surround a portion of the second lead wire 420. The lead wire 400 may be insulated from the housing 100 via the insulating layer 500. The lead wire 400 and the housing 100 may be easily connected via the insulating layer 500 and the sealing layer. The first lead wire 410 and the second lead wire 420 may be insulated via the insulating layer 500.

[0069] Figure 2 This is a side view of an electrode assembly according to some embodiments of the present disclosure.

[0070] The electrode assembly 200 can be formed in a stacked manner. The first electrode 210, the second electrode 220, and the diaphragm 230 can be stacked. For example, the electrode assembly 200 can be a Z-stacked electrode assembly. Accordingly, the diaphragm 230 is disposed between the first electrode 210 and the second electrode 220.

[0071] The first electrode 210 may include a first current collector 211 having a first uncoated portion 211a and a first active material layer 212 on the first current collector 211. The first active material layer 212 may be disposed on a region other than the first uncoated portion 211a. The first uncoated portion 211a may be a first electrode tab 310. The first active material layer 212 may be disposed on at least one of one surface and another surface of the first current collector 211.

[0072] The first active material layer 212 may include a positive electrode active material. As the positive electrode active material, a compound capable of reversibly inserting / deintercalating lithium (e.g., a lithiated intercalation compound) may be used. For example, at least one of lithium and a composite oxide of a metal selected from cobalt, manganese, nickel, and combinations thereof may be used.

[0073] The composite oxide can be a lithium transition metal composite oxide, and examples of it can include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0074] As an example, the following compounds, represented by any of the following chemical formulas, can be used. Li a A 1-b X b O 2- c D c (0.90≤a≤1.8, 0≤b≤0.5 and 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5 and 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5 and 0<α<2); Li a Ni 1-b-c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5 and 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5 and 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8 and 0.001≤b≤0.1); Li a CoG b O2 (0.90≤a≤1.8 and 0.001≤b≤0.1); Li a Mn 1-b G b O2 (0.90≤a≤1.8 and 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8 and 0.001≤b≤0.1); Li a Mn1- g G g PO4 (0.90 ≤ a ≤ 1.8 and 0 ≤ g ≤ 0.5); Li (3-f) Fe2(PO4)3 (0≤f≤2) and Li a FePO4 (0.90≤a≤1.8).

[0075] In the above chemical formulas, A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, or a combination thereof; D is O, F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L 1 It is Mn, Al, or a combination thereof.

[0076] The positive electrode for a lithium secondary battery may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer may include a positive electrode active material and may further include a binder and / or a conductive material.

[0077] Based on a 100wt% positive electrode active material layer, the content of the positive electrode active material is in the range of about 90wt% to about 99.5wt%, and based on the 100wt% positive electrode active material layer, the contents of the binder and conductive material are in the range of about 0.5wt% to about 5wt%, respectively.

[0078] The current collector can be aluminum (Al), but is not limited to this.

[0079] The second electrode 220 may include (i) a second current collector 221 including a second uncoated portion 221a and (ii) a second active material layer 222 on the second current collector 221. The second active material layer 222 may be disposed on a region other than the second uncoated portion 221a. The second uncoated portion 221a may be a second electrode tab 320. The second active material layer 222 may be disposed on at least one of one surface and another surface of the second current collector 221.

[0080] The second active material layer 222 may include a negative electrode active material. The negative electrode active material may include a material capable of reversibly inserting / deintercalating lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0081] Materials capable of reversibly inserting / deintercalating lithium ions can be carbon-based negative electrode active materials, which may include, for example, crystalline carbon, amorphous carbon, or combinations thereof. Examples of crystalline carbon may include graphite, such as natural or artificial graphite, and examples of amorphous carbon may include soft carbon, hard carbon, pitch carbides (e.g., mesophase pitch carbides), calcined coke, etc.

[0082] Si-based negative electrode active material or Sn-based negative electrode active material can be used as a material capable of doping and de-doping lithium. The Si-based negative electrode active material can be silicon, silicon-carbon composite, SiO x (0 < x ≤ 2), Si-based alloy or a combination thereof.

[0083] The silicon-carbon composite can be a composite of silicon and amorphous carbon. According to one embodiment, the silicon-carbon composite can be in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0084] The silicon-carbon composite can further include crystalline carbon. For example, the silicon-carbon composite can include a core containing crystalline carbon and silicon particles and an amorphous carbon coating on the surface of the core.

[0085] The negative electrode for a lithium secondary battery can include a current collector and a negative electrode active material layer provided on the current collector. The negative electrode active material layer can include a negative electrode active material and can further include a binder and / or a conductive material.

[0086] For example, the negative electrode active material layer can include about 90 wt% to about 99 wt% of the negative electrode active material, about 0.5 wt% to about 5 wt% of the binder, and about 0 wt% to about 5 wt% of the conductive material.

[0087] A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used as the binder. When an aqueous binder is used as the negative electrode binder, a cellulose-based compound capable of imparting viscosity can be further included.

[0088] As the negative electrode current collector, one selected from copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive metal, and a combination thereof can be used.

[0089] The electrolyte for a lithium secondary battery can include a non-aqueous organic solvent and a lithium salt.

[0090] The non-aqueous organic solvent serves as a medium through which ions participating in the electrochemical reaction of the battery can move.

[0091] The non-aqueous organic solvent can be a carbonate solvent, an ester solvent, an ether solvent, a ketone solvent, an alcohol solvent, an aprotic solvent, and can be used alone or in combination of two or more.

[0092] In addition, when using a carbonate solvent, a mixture of cyclic carbonate and chain carbonate can be used.

[0093] Depending on the type of lithium secondary battery, a separator may be present between the first electrode plate (e.g., the positive electrode) and the second electrode plate (e.g., the negative electrode). As the separator, polyethylene, polypropylene, polyvinylidene fluoride, or multilayer films of two or more layers thereof may be used.

[0094] The diaphragm may include a porous substrate and a coating on one or both surfaces of the porous substrate, comprising organic materials, inorganic materials, or combinations thereof.

[0095] Organic materials may include polyvinylidene fluoride-based heavy antibodies or (meth)acrylic acid polymers.

[0096] Inorganic materials may include, but are not limited to, inorganic particles selected from Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite and combinations thereof.

[0097] Organic and inorganic materials can be mixed in a single coating, or they can be in the form of coatings containing organic materials and coatings containing inorganic materials layered on top of each other.

[0098] The first electrode 210 and the second electrode 220 may have different sizes. Specifically, in some embodiments, the areas of the first electrode 210 and the second electrode 220 may be different. Correspondingly, the sizes of the first active material layer 212 and the second active material layer 222 may be different. Specifically, in some embodiments, the area of ​​the second active material layer 222 may be larger than the area of ​​the first active material layer 212.

[0099] Generally, the positive electrode has a higher capacity than the negative electrode, and the lithium insertion / extraction rate is faster. Consequently, when the lithium-ion storage capacity in the negative electrode is insufficient, not all lithium ions from the positive electrode are inserted into the negative electrode. Therefore, dendrite formation of lithium on the negative electrode may occur. As the dendrites grow, they may damage the separator. Consequently, the first electrode 210 and the second electrode 220 may short-circuit. To solve the aforementioned problem, the second electrode 220 can be formed to be larger than the first electrode 210. Accordingly, the capacity of the second electrode 220 is increased, thereby reducing or preventing dendrite formation.

[0100] The size of the diaphragm 230 may differ from the sizes of the electrodes 210 and 220. The size of the diaphragm 230 may be larger than the sizes of the electrodes 210 and 220. Accordingly, the diaphragm 230 may be configured to cover both the first electrode 210 and the second electrode 220. Therefore, short circuits between the first electrode 210 and the second electrode 220 due to errors during the manufacturing process can be prevented.

[0101] Electrode assembly 200 can be tested after manufacturing. For example, because electrode assembly 200 can generate heat during use, its thermal properties can be tested at a set temperature. Accordingly, diaphragm 230 may deform due to heat. For example, if the temperature of the heat generated during testing or use is higher than the melting temperature of the diaphragm, the diaphragm may shrink. Accordingly, the first electrode and the second electrode may come into contact. Accordingly, the electrode assembly may cause a fire due to a short circuit between the first electrode and the second electrode.

[0102] In some embodiments, the electrode assembly may include a protective layer 600. The protective layer can reduce or prevent diaphragm shrinkage. Therefore, the safety of the electrode assembly can be improved. In some embodiments, the protective layer 600 may be a heat-resistant layer.

[0103] refer to Figures 2-8 A protective layer 600 may be disposed on the diaphragm 230. For example, the protective layer 600 may be disposed on at least one of a surface (e.g., the top surface) and another surface (e.g., the bottom surface) of the diaphragm 230. In some embodiments, the protective layer 600 may include at least one of a first protective layer 610 and a second protective layer 620. The first protective layer 610 may be a protective layer adjacent to the first active material layer 212. The second protective layer 620 may be a protective layer adjacent to the second active material layer 222.

[0104] As described above, the size of the diaphragm 230 may be larger than the size of the first electrode 210 and the second electrode 220. Therefore, the diaphragm 230 may include protrusions. In some embodiments, the protrusions may protrude relative to the first electrode 210 and the second electrode 220. For example, the diaphragm 230 may include a first protrusion PA1 (see example...). Figure 3 ) and the second protrusion PA2 (see example) Figure 3 The first protrusion PA1 may be an area that overlaps with the electrode contact piece 300. The second protrusion PA2 may be an area that does not overlap with the electrode contact piece 300.

[0105] Figure 3 This is a top view of an electrode assembly according to some embodiments of the present disclosure.

[0106] The diaphragm 230 includes a first protrusion PA1 and a second protrusion PA2. However, the embodiments are not limited thereto; for example, the diaphragm 230 may include at least one of the first protrusion PA1 and the second protrusion PA2.

[0107] A protective layer 600 may be disposed on at least one of the first protrusion PA1 and the second protrusion PA2. In some embodiments, the protective layer 600 may be disposed on the first protrusion PA1. The protective layer 600 may be spaced apart from the electrodes 210 and 220. Accordingly, the protective layer may prevent a decrease in the capacity of the electrodes. The protective layer 600 may contact or be spaced apart from the end E of the diaphragm 230.

[0108] The protective layer 600 may include a non-conductive material. The protective layer 600 may have a set melting temperature. In some embodiments, the melting temperature of the protective layer may be higher than the temperature at which the thermal properties of the electrode assembly are tested. For example, the melting temperature of the protective layer may be 130°C to 900°C, 140°C to 850°C, or 150°C to 800°C. The protective layer 600 may include various materials having melting temperatures within the above ranges. In some embodiments, the protective layer 600 may be (or include) polyimide (PI), polypropylene (PP), or an ionomer thermoplastic resin (surlyn resin). Ionomers may have various melting temperatures depending on their composition. Preferably, the protective layer 600 may include polyimide (PI) or polypropylene.

[0109] Figures 4-8 According to some embodiments of this disclosure Figure 3 A cross-sectional view taken from line A-A'.

[0110] refer to Figure 4 The protective layer 600 can be disposed on one surface of the diaphragm 230.

[0111] The protective layer 600 may have a set thickness. The thickness T of the protective layer 600 may be greater than or equal to the thickness of the separator 230. The thickness T of the protective layer 600 may be less than or equal to the thickness of the active material layer. In some embodiments, when the protective layer includes a first protective layer 610, the thickness T of the protective layer may be less than or equal to the thickness of the first active material layer. When the protective layer includes a second protective layer 620, the thickness T of the protective layer may be less than or equal to the thickness of the second active material layer.

[0112] The thickness of the membrane can be 8 μm to 12 μm. The thickness of the first active material layer can be 75 μm to 95 μm. The thickness of the second active material layer can be 100 μm to 120 μm.

[0113] Because the thickness T of the protective layer is controlled within at least one of the set ranges, the thickness of the electrode assembly is prevented from increasing due to the protective layer.

[0114] refer to Figure 5 The protective layer 600 may be disposed on both surfaces of the diaphragm 230. The protective layer 600 may include a first protective layer 610 and a second protective layer 620.

[0115] The area of ​​the diaphragm 230 may be defined by the electrode tabs 300. In particular, in some embodiments, the diaphragm 230 may include overlapping regions that overlap with the electrode tabs 300. For example, the diaphragm 230 (e.g., the overlapping regions) may include a first overlapping region OA1 that overlaps with the first electrode tab 310 and a second overlapping region OA2 that overlaps with the second electrode tab 320.

[0116] The protective layer 600 may have a set thickness. Further, the thickness of the first protective layer may be greater than or equal to the thickness of the separator and less than or equal to the thickness of the first active material layer. The thickness of the second protective layer may be greater than or equal to the thickness of the separator and less than or equal to the thickness of the second active material layer.

[0117] Therefore, the thickness of the first protective layer 610 and the thickness of the second protective layer 620 can be the same or different. In some embodiments, the thickness of the second protective layer 620 can be greater than or equal to the thickness of the first protective layer 610. Furthermore, the thickness of the second active material layer can be greater than the thickness of the first active material layer.

[0118] Because the thickness of the first and second protective layers is controlled within a set range, the thickness of the electrode assembly can be prevented from increasing due to the protective layers.

[0119] The first protective layer 610 may have a first-1 thickness T1-1 and a first-2 thickness T1-2. The first-1 thickness T1-1 may be the thickness at the first overlapping region OA1. The first-2 thickness T1-2 may be the thickness at the region other than the first overlapping region OA1.

[0120] The second protective layer 620 may have a second-first thickness T2-1 and a second-second thickness T2-2. The second-first thickness T2-1 may be the thickness at the second overlapping region OA2. The second-second thickness T2-2 may be the thickness in the region other than the second overlapping region OA2.

[0121] Thickness T1-1 (1-1) and thickness T1-2 (1-2) can be the same or similar. Similarly, thickness T2-1 (2-1) and thickness T2-2 (2-2) can be the same or similar. Accordingly, the first protective layer 610 and the second protective layer 620 can be readily formed, for example, by forming them in one process.

[0122] refer to Figures 6-8 The first protective layer 610 and the second protective layer 620 may include regions with different thicknesses.

[0123] refer to Figure 6 and Figure 7The first protective layer 610 may include regions with different thicknesses. For example, the first-1 thickness T1-1 and the first-2 thickness T1-2 may be different. In particular, in some embodiments, the first-1 thickness T1-1 may be greater than the first-2 thickness T1-2.

[0124] The second protective layer 620 may include regions with different thicknesses. For example, the second-first thickness T2-1 and the second-second thickness T2-2 may be different. In particular, in some embodiments, the second-first thickness T2-1 may be greater than the second-second thickness T2-2.

[0125] The first overlapping region OA1 and the second overlapping region OA2 are regions that overlap with the electrode contact piece 300. The electrode contact piece 300 includes a conductive material. Accordingly, the temperature of the region of the diaphragm that overlaps with the electrode contact piece 300 can be higher than the temperature of other regions of the diaphragm. Consequently, the overlapping region is more likely to shrink than other regions.

[0126] Therefore, the thickness T1-1 of the first-1 layer can be greater than the thickness T1-2 of the first-2 layer, and the thickness T2-1 of the second-1 layer can be greater than the thickness T2-2 of the second-2 layer. Accordingly, the first overlapping region OA1 and the second overlapping region OA2 can be easily protected by the first protective layer 610 and the second protective layer 620, respectively.

[0127] refer to Figure 6 and Figure 7 The thicknesses T1-1 (first-first) and T2-1 (second-first) can be different.

[0128] refer to Figure 6 The thickness T2-1 of the second protective layer can be greater than the thickness T1-1 of the first protective layer. As described above, the thickness of the second protective layer can be greater than the thickness of the first protective layer. Accordingly, the thickness T2-1 of the second protective layer, which is the maximum thickness of the second protective layer, can be greater than the thickness T1-1 of the first protective layer, which is the maximum thickness of the first protective layer.

[0129] refer to Figure 7 The thickness T1-1 of the first electrode terminal block 310 may be greater than the thickness T2-1 of the second electrode terminal block 320. The first electrode terminal block 310 and the second electrode terminal block 320 may be made of different materials. The first electrode terminal block 310 may be made of a material with a higher thermal conductivity than the second electrode terminal block 320. For example, the first electrode terminal block 310 may be made of aluminum, and the second electrode terminal block 320 may be made of copper or nickel.

[0130] Therefore, due to the first electrode tab 310, the temperature of the first overlapping region OA1 can be higher than the temperature of the second overlapping region OA2. Therefore, the first overlapping region OA1 can contract more than the second overlapping region OA2.

[0131] Accordingly, the first-1 thickness T1-1 can be greater than the second-1 thickness T2-1. Accordingly, shrinkage of the first overlapping region OA1 can be reduced or prevented. In some embodiments, the thickness of the first protective layer 610 can be greater than or equal to the thickness of the second protective layer 620.

[0132] refer to Figure 8 The first protective layer 610 may include regions with different thicknesses. The first protective layer 610 may further include a region having a first-third thickness T1-3. The region having a first-third thickness T1-3 may be the region corresponding to the second overlapping region OA2. The region having a first-first thickness T1-1 is the region overlapping with the first electrode contact 310, and the region having a first-third thickness T1-3 is the region overlapping with the second electrode contact 320. Because the region having a first-first thickness T1-1 directly faces the first electrode contact 310, heat generated from the first electrode contact 310 can be directly transferred. The region having a first-third thickness T1-3 indirectly faces the second electrode contact 320. Therefore, heat generated in the second electrode contact 320 can be transferred to the region having a first-third thickness T1-3. Therefore, the first-first thickness T1-1 and the first-third thickness T1-3 may be greater than the first-second thickness T1-2.

[0133] The second protective layer 620 may include regions with different thicknesses. The second protective layer 620 may further include a region having a second-third thickness T2-3. The region having a second-third thickness T2-3 may be the region corresponding to the first overlapping region OA1. The region having a second-first thickness T2-1 is the region overlapping with the second electrode contact 320, and the region having a second-third thickness T2-3 is the region overlapping with the first electrode contact 310. Because the region having a second-first thickness T2-1 directly faces the second electrode contact 320, heat generated from the second electrode contact 320 can be directly transferred. The region having a second-third thickness T2-3 indirectly faces the first electrode contact 310. Therefore, heat generated from the first electrode contact 310 can be transferred to the region having a second-third thickness T2-3. Therefore, the second-first thickness T2-1 and the second-third thickness T2-3 may be greater than the second-second thickness T2-2.

[0134] As described above, the temperature of the overlapping area of ​​the electrode terminals on the diaphragm can be higher than the temperature of other areas of the diaphragm. Accordingly, the thickness of the first and second protective layers corresponding to the overlapping area can be increased. This reduces or prevents shrinkage of the overlapping area.

[0135] The sum of thickness T1-1 (1-1) and thickness T2-3 (2-3) can be different from the sum of thickness T1-3 (1-3) and thickness T2-1 (2-1). The sum of thickness T1-1 (1-1) and thickness T2-3 (2-3) can be greater than the sum of thickness T1-3 (1-3) and thickness T2-1 (2-1).

[0136] As described above, the first electrode terminal 310 may comprise a material having a higher thermal conductivity than the second electrode terminal 320. Therefore, due to the first electrode terminal 310, the temperature of the first overlapping region OA1 may be higher than the temperature of the second overlapping region OA2. Consequently, the first overlapping region OA1 is more likely to contract than the second overlapping region OA2.

[0137] Accordingly, the sum of the first-1 thickness T1-1 and the second-3 thickness T2-3 can be greater than the sum of the first-3 thickness T1-3 and the second-1 thickness T2-1. Therefore, the shrinkage of the first overlapping region OA1 can be reduced or prevented.

[0138] Figure 9 According to some embodiments of this disclosure Figure 3 The cross-sectional view taken by line B-B'.

[0139] The first protective layer and the second protective layer can be connected. The protective layer 600 can be disposed on the top surface 232, bottom surface 234 and side surface 236 of the diaphragm 230. Therefore, the first protective layer and the second protective layer can be integrally formed.

[0140] Therefore, a protective layer can be easily formed. This protective layer can be formed on the top surface 232 and bottom surface 234 of the diaphragm in a single process. This improves the process efficiency of the electrode assembly.

[0141] In the above description, it has been shown that the first electrode terminal block and the second electrode terminal block extend in the same direction. However, the embodiments are not limited thereto, and the first electrode terminal block 310 and the second electrode terminal block 320 may extend in opposite directions.

[0142] Accordingly, the first protrusion may include a first-1 protrusion overlapping the first electrode tab and a first-2 protrusion overlapping the second electrode tab. The protective layer may include a first-1 protective layer on the first-1 protrusion and a first-2 protective layer on the first-2 protrusion.

[0143] The first-1 protective layer and the first-2 protective layer may each include regions with different thicknesses. In some embodiments, the thickness of the first-1 protective layer in the region overlapping with the first electrode tab may be greater than the thickness of the first-1 protective layer in another region. The thickness of the first-2 protective layer in the region overlapping with the second electrode tab may be greater than the thickness of the first-2 protective layer in another region. Accordingly, shrinkage of the diaphragm overlapping with the electrode tab can be reduced or prevented.

[0144] In some embodiments, the thicknesses of the first-1 protective layer and the first-2 protective layer may be the same or similar. In other embodiments, the thicknesses of the first-1 protective layer and the first-2 protective layer may be different. In some embodiments, the thickness of the first-1 protective layer may be greater than the thickness of the first-2 protective layer. Accordingly, shrinkage of the first protrusion caused by the material of the first electrode tab can be reduced or prevented.

[0145] In some embodiments, the electrode assembly includes a protective layer. The protective layer is disposed on a protrusion of the diaphragm.

[0146] The protective layer comprises a material having a melting temperature within a defined range. A diaphragm may be protected by the protective layer. The protective layer reduces or prevents heat generated during testing or use of the electrode assembly from being transferred to the diaphragm. Accordingly, it prevents the diaphragm from shrinking due to heat. Accordingly, the diaphragm prevents short circuits between the first and second electrodes. Accordingly, it prevents fires within the electrode assembly, thereby improving the safety of the electrode assembly.

[0147] The protective layer can have varying thicknesses depending on the region. The temperature of the diaphragm in the region overlapping with the electrode terminals can be higher than the temperature of the diaphragm in another region. Accordingly, the thickness of the protective layer in the region overlapping with the electrode terminals can be greater than the thickness of the protective layer in another region. Consequently, shrinkage of the diaphragm in the region overlapping with the electrode terminals can be reduced or prevented.

[0148] The temperature of the diaphragm in the region overlapping with the first electrode terminal can be higher than the temperature of the diaphragm in the region overlapping with the second electrode terminal. Correspondingly, the thickness of the protective layer in the region overlapping with the first electrode terminal can be greater than the thickness of the protective layer in the region overlapping with the second electrode terminal. This reduces or prevents shrinkage of the diaphragm in the region overlapping with the first electrode terminal.

[0149] The following text will refer to Figures 10-13 Electrode assemblies according to some embodiments are described. Commonalities with the embodiments described above will be omitted. Additionally, Figures 10-13 The same or similar reference numerals in the figures are consistent with the same or similar aspects of the reference numerals found above.

[0150] Figures 10-14This is a top view of an electrode assembly according to some embodiments of the present disclosure.

[0151] The protective layer may include multiple patterns. For example, the protective layer may include a first pattern P1 and a second pattern P2. Further, at least one of the first protective layer 610 and the second protective layer 620 may include the first pattern P1 and the second pattern P2. The first pattern P1 may overlap with the first electrode contact 310. The second pattern P2 may overlap with the second electrode contact 320. The first pattern P1 and the second pattern P2 may be spaced apart from each other.

[0152] As described above, the diaphragm 230 can easily shrink in the area overlapping with the electrode tabs. Accordingly, the first pattern P1 and the second pattern P2 can be configured to overlap with the electrode tabs.

[0153] The protective layer 600 may be adjacent to the end E of the diaphragm. Therefore, the end of the diaphragm 230 may be bent due to the protective layer 600. In some embodiments, the electrode assembly includes a protective layer formed with multiple patterns. Therefore, bending of the diaphragm in one direction due to the protective layer can be reduced or prevented.

[0154] refer to Figure 11 and Figure 12 The protective layer 600 may include multiple protective layers. For example, the protective layer 600 may include a first-a protective layer 600a and a second-a protective layer 600b. Further, at least one of the first protective layer 610 and the second protective layer 620 may include a first-a protective layer 600a and a second-a protective layer 600b. The second-a protective layer 600b may be adjacent to (or close to) an electrode (e.g., the first electrode 210 or the second electrode 220) than the first-a protective layer 600a. Therefore, the second-a protective layer 600b may be disposed between the first-a protective layer 600a and the active material layer.

[0155] The first-a protective layer 600a may be the primary protective layer. The second-a protective layer 600b may be the secondary protective layer. The second-a protective layer 600b may include at least one protective layer.

[0156] The first-a protective layer 600a and the second-a protective layer 600b may have different dimensions. For example, the width W1 of the first-a protective layer 600a may be greater than the width W2 of the second-a protective layer 600b.

[0157] Shrinkage of the diaphragm 230 can be primarily prevented by the first-a protective layer 600a. However, the adhesive properties of the first-a protective layer 600a may be reduced due to errors during the process. Consequently, the first-a protective layer 600a may peel off when the electrode assembly is used. Shrinkage of the diaphragm 230 can be secondary prevented by the second-a protective layer 600b.

[0158] Therefore, the diaphragm can be stably protected. In some embodiments, the diaphragm may include multiple protective layers. Accordingly, even if a defect occurs in one protective layer, the diaphragm can be protected by another protective layer. Thus, fires of the electrode assembly can be prevented.

[0159] refer to Figure 12 The first-a protective layer 600a and the second-a protective layer 600b can be formed into different shapes.

[0160] The first-a protective layer 600a may be disposed on both the area overlapping with the electrode terminals and the area not overlapping with the electrode terminals. The second-a protective layer 600b may include a plurality of patterns P disposed on the area overlapping with the electrode terminals.

[0161] As mentioned above, the area of ​​the diaphragm that overlaps with the electrode terminals is prone to shrinkage. Therefore, multiple protective layers can be provided on the area overlapping with the electrode terminals. Thus, diaphragm shrinkage can be reduced or prevented.

[0162] refer to Figure 13 and Figure 14 The protective layer may include a first-b protective layer 601 and a second-b protective layer 602. Further, at least one of the first protective layer 610 and the second protective layer 620 may include the first-b protective layer 601 and the second-b protective layer 602.

[0163] The first-b protective layer 601 and the second-b protective layer 602 may extend in different directions. In particular, in some embodiments, the first-b protective layer 601 and the second-b protective layer 602 may extend in directions perpendicular to each other. The first-b protective layer 601 may be disposed on the first protrusion PA1. The second-b protective layer 602 may be disposed on the second protrusion PA2.

[0164] refer to Figure 13 The first-b protective layer 601 and the second-b protective layer 602 may be spaced apart. (See reference) Figure 14 The first-b protective layer 601 and the second-b protective layer 602 can be connected to each other and formed integrally.

[0165] The contraction of the second protrusion of the diaphragm can be prevented by the second-b protective layer 602.

[0166] The first-b protective layer 601 and the second-b protective layer 602 may have different dimensions. For example, the width of the first-b protective layer 601 may be greater than the width of the second-b protective layer 602. The first-b protective layer 601 may overlap with the electrode tab. Accordingly, the first protrusion PA1 is more likely to shrink than the second protrusion PA2. Therefore, the first-b protective layer 601 may be formed to be larger than the second-b protective layer 602. This improves the safety of the electrode assembly.

[0167] Figure 15 An example of an electrode assembly according to some embodiments of the present disclosure is applied to another type of secondary battery.

[0168] The electrode assembly according to the above embodiments can be applied to secondary batteries having various shapes. For example, in some embodiments, the electrode assembly can be applied to... Figure 1 A pouch-shaped secondary battery. In other embodiments, the electrode assembly can be applied to... Figure 15 The secondary battery 1000 is prismatic in shape. Therefore, the electrode assembly can be housed in the prismatic housing 1100.

[0169] Figure 16 This is a perspective view of a battery module including a secondary battery according to some embodiments of the present disclosure.

[0170] refer to Figure 16 A battery module 2000 according to one or more exemplary embodiments of the present disclosure includes terminal portions 261, 262, a plurality of secondary batteries 1000 arranged in one direction, a connecting tab 20 connecting a secondary battery 1000a to an adjacent secondary battery 1000b, and a protection circuit module 30 having one end connected to the connecting tab 20. The protection circuit module 30 may include a battery management system (BMS). Further, the connecting tab 20 may include a body portion that contacts the terminal portions 261, 262 between adjacent secondary batteries 1000a, 1000b, and an extension portion extending from the body portion and connected to the protection circuit module 30. The connecting tab 20 may be, for example, a busbar.

[0171] Each secondary battery 1000 may include a battery casing, an electrode assembly received (or housed) within the battery casing, and an electrolyte. The electrode assembly and electrolyte undergo an electrochemical reaction to store and release (e.g., generate) energy. Terminals 261, 262 electrically connected to connecting tabs 20, and an exhaust port 850 serving as a channel for venting gas generated inside the battery casing, may be provided on one side (e.g., the upper side) of the secondary battery 1000. Terminals 261, 262 of the secondary battery 1000 may be positive electrode terminals 261 and negative electrode terminals 262 with different polarities, and the terminals 261, 262 of adjacent secondary batteries 1000a, 1000b may be electrically connected in series or parallel via connecting tabs 20, as will be described in more detail below. Although series connection has been described as an example, the connection structure is not limited thereto, and various connection structures may be employed as desired or required. Furthermore, the number and arrangement of secondary batteries are not limited to... Figure 16 The structure shown is available and can be changed as desired or required.

[0172] Multiple secondary batteries 1000 may be arranged in one direction (e.g., stacked in one direction) such that the wide surfaces of the secondary batteries 1000 face each other, and the multiple secondary batteries 1000 may be secured by housings 61, 62, 63, and 64. Housings 61, 62, 63, and 64 may include a pair of end plates 61, 62 facing the wide surfaces of the secondary batteries 1000, and a side plate 63 and a bottom plate 64 connecting the pair of end plates 61, 62 to each other. The side plate 63 may support the side surfaces of the secondary batteries 1000, and the bottom plate 64 may support the bottom surface of the secondary batteries 1000. Furthermore, the pair of end plates 61, 62, the side plate 63, and the bottom plate 64 may be connected by bolts 65 and / or any other suitable fastening members and methods known to those skilled in the art.

[0173] The protection circuit module 30 may have electronic components and protection circuitry mounted thereon, and may be electrically connected to the connecting tabs 20, which will be described in more detail later. The protection circuit module 30 includes a first protection circuit module 30a and a second protection circuit module 30b extending along a direction in which the plurality of secondary batteries 1000 are arranged at different locations. The first protection circuit module 30a and the second protection circuit module 30b may be spaced apart from each other at a suitable or desired interval (e.g., a predetermined interval) and arranged parallel to each other to be electrically connected to adjacent connecting tabs 20, respectively. For example, the first protection circuit module 30a extends along the direction in which the plurality of secondary batteries 1000 are arranged on one side of the upper portion of the plurality of secondary batteries 1000, and the second protection circuit module 30b extends along the direction in which the plurality of secondary batteries 1000 are arranged to the other upper side of the plurality of secondary batteries 1000. The second protection circuit module 30b may be spaced apart from the first protection circuit module 30a at a suitable or desired interval (e.g., a predetermined interval) (with an exhaust port 850 between them), but may be configured to be parallel to the first protection circuit module 30a. Thus, the two protection circuit modules are arranged side-by-side and spaced apart from each other along the direction in which the multiple secondary batteries 1000 are arranged, thereby reducing or minimizing the area of ​​the printed circuit board (PCB) constituting the protection circuit module. By configuring the protection circuit module as two separate protection circuit modules, the unnecessary protection circuit module area can be reduced or minimized. In addition, the first protection circuit module 30a and the second protection circuit module 30b can be connected to each other via a conductive connecting member 50. One side of the conductive connecting member 50 is connected to the first protection circuit module 30a, and the other side is connected to the second protection circuit module 30b, so that the two protection circuit modules 30a and 30b can be electrically connected to each other.

[0174] The connection can be performed by any of the following methods: brazing, resistance welding, laser welding, projection welding, and / or any other suitable connection method known to those skilled in the art.

[0175] Additionally, the connecting member 50 may be, for example, a wire. Furthermore, the connecting member 50 may be made of or include a resilient or flexible material. Through the connecting member 50, the voltage, temperature, and / or current of multiple secondary batteries 1000 can be checked and managed to ensure they are normal or within desired ranges. For example, information (such as voltage, current, and / or temperature) received by the first protection circuit module from the connecting tab adjacent to the first protection circuit module, and information (such as voltage, current, and / or temperature) received from the connecting tab adjacent to the second protection circuit module, can be integrated and managed by the protection circuit module through the connecting member 50.

[0176] In addition, when the secondary battery 1000 expands, the impact can be absorbed by the elasticity or flexibility of the connecting member 50, thereby preventing or avoiding damage to the first protection circuit module 30a and the second protection circuit module 30b.

[0177] Furthermore, the shape and structure of the connecting member 50 are not limited to... Figure 16 The shapes and structures shown.

[0178] As described above, since the protection circuit module 30 is provided as a first protection circuit module 30a and a second protection circuit module 30b, the area of ​​the PCB constituting the protection circuit module can be reduced or minimized, and the space inside the battery module can be ensured. This improves work efficiency by facilitating the fastening of the connecting terminals 20 and the protection circuit module 30 and the maintenance work when an abnormality is detected in the battery module.

[0179] The secondary battery and battery module according to the previously described example embodiments can be used to manufacture battery packs.

[0180] Figure 17 and Figure 18 This is a perspective view of a battery pack including battery modules according to some embodiments of the present disclosure. The battery pack 3000 may include a plurality of battery modules 3200 and a housing 3100 for receiving the plurality of battery modules 3200. For example, the housing 3100 may include a first housing 3110 and a second housing 3120 connected in opposite directions via the plurality of battery modules 3200. The plurality of battery modules 3200 may be electrically connected to each other using busbars 3500, and the plurality of battery modules 3200 may be electrically connected to each other in series / parallel or a hybrid series-parallel configuration to obtain a desired (e.g., required) electrical output. In the drawings, components such as busbars, cooling units, and external terminals for electrical connections to secondary batteries are omitted for illustrative purposes. In one or more example embodiments, the battery pack 3000 may be installed in a vehicle. The vehicle may be, or include, for example, an electric vehicle or a hybrid vehicle (e.g., a plug-in hybrid vehicle). The vehicle may include a four-wheeled vehicle or a two-wheeled vehicle.

[0181] Figure 19 This is a perspective view of a vehicle including a battery pack according to some embodiments of the present disclosure.

[0182] exist Figure 19 In this configuration, the battery pack 3000 may include a battery pack cover 3010 and a battery pack frame 3020. The battery pack cover 3010 is part of the vehicle floor 4100 and may correspond to a first housing. The battery pack frame 3020 is disposed below the vehicle floor 4100 and may correspond to a second housing. The battery pack cover 3010 and the battery pack frame 3020 may be integrally formed, for example, with the vehicle floor 4200. The vehicle floor 4100 separates the interior and exterior of the vehicle, and the battery pack frame 3020 may be disposed on the exterior of the vehicle.

[0183] Figure 20 A side view of a vehicle including a battery pack according to some embodiments of the present disclosure.

[0184] exist Figure 20 In this embodiment, vehicle 4000 can be formed by attaching additional components such as an engine hood 4300 at the front of vehicle 4000 and fenders 4400 located at the front and rear of vehicle 4000 to the vehicle body. Vehicle 4000 may include battery pack 3000, which includes battery pack cover 3010 and pack frame 3020, and battery pack 3000 can be connected to vehicle body.

[0185] The foregoing description details some embodiments for implementing the secondary battery according to this disclosure, but this disclosure is not limited to the embodiments discussed above. Various modifications can be made by anyone skilled in the art to which this disclosure pertains without departing from the teachings of this disclosure.

Claims

1. An electrode assembly, comprising: First electrode; Second electrode; as well as A diaphragm is located between the first electrode and the second electrode. The diaphragm includes a protrusion that protrudes relative to the first electrode and the second electrode, and a protective layer is disposed on the protrusion.

2. The electrode assembly of claim 1, wherein the protective layer is disposed on at least one of the top surface and the bottom surface of the diaphragm.

3. The electrode assembly of claim 1, wherein the protective layer is spaced apart from the first electrode and the second electrode.

4. The electrode assembly according to claim 1, wherein the melting temperature of the protective layer is 130°C to 900°C.

5. The electrode assembly of claim 1, wherein the protective layer comprises polyimide, polypropylene, or an ionomer.

6. The electrode assembly according to any one of claims 1 to 5, wherein the first electrode comprises a first current collector and a first active material layer on the first current collector. The second electrode includes a second current collector and a second active material layer on the second current collector, and The protective layer includes a first protective layer adjacent to the first active material layer and a second protective layer adjacent to the second active material layer.

7. The electrode assembly of claim 6, wherein the thickness of the first protective layer is greater than or equal to the thickness of the separator and less than or equal to the thickness of the first active material layer, and the thickness of the second protective layer is greater than or equal to the thickness of the separator and less than or equal to the thickness of the second active material layer.

8. The electrode assembly of claim 6, wherein the first protective layer includes a region having a thickness different from the thickness of another region of the first protective layer, and / or the second protective layer includes a region having a thickness different from the thickness of another region of the second protective layer.

9. The electrode assembly of claim 1, wherein the protective layer comprises a first-a protective layer and a second-a protective layer, the second-a protective layer being closer to the first electrode or the second electrode than the first-a protective layer, and the width of the first-a protective layer being greater than the width of the second-a protective layer.

10. A secondary battery, comprising: case; An electrode assembly, housed within the housing, the electrode assembly comprising: First electrode; Second electrode; and A diaphragm is located between the first electrode and the second electrode; Electrode terminals are connected to the electrode assembly; and Lead wires are connected to the electrode terminals. The diaphragm includes a protrusion that protrudes relative to the first electrode and the second electrode, and a protective layer is disposed on the protrusion.

11. The secondary battery according to claim 10, wherein the protrusion includes at least one of a first protrusion overlapping the electrode tab and a second protrusion not overlapping the electrode tab.

12. The secondary battery according to claim 11, wherein the protective layer is disposed on the first protrusion, and The protective layer is disposed on at least one of the top and bottom surfaces of the diaphragm.

13. The secondary battery of claim 10, wherein the separator includes an overlapping region that overlaps with the electrode terminals. The first electrode includes a first current collector and a first active material layer on the first current collector, the second electrode includes a second current collector and a second active material layer on the second current collector, the protective layer includes a first protective layer adjacent to the first active material layer and a second protective layer adjacent to the second active material layer, and the first protective layer includes a region having a thickness different from the thickness of another region of the first protective layer, and / or the second protective layer includes a region having a thickness different from the thickness of another region of the second protective layer.

14. The secondary battery according to claim 13, wherein the electrode terminals include a first electrode terminal connected to the first electrode and a second electrode terminal connected to the second electrode. The overlapping region includes a first overlapping region overlapping the first electrode tab and a second overlapping region overlapping the second electrode tab. The first protective layer has a first-1 thickness at the first overlapping region and a first-2 thickness in the region excluding the first overlapping region. The second protective layer has a second-1 thickness at the second overlapping region and a second-2 thickness in the region excluding the second overlapping region. The thickness of the first-1 is greater than the thickness of the first-2, and the thickness of the second-1 is greater than the thickness of the second-2.

15. The secondary battery according to claim 13, wherein the first electrode is a positive electrode, the second electrode is a negative electrode, and the thickness of the first protective layer is greater than or equal to the thickness of the second protective layer.

16. The secondary battery according to claim 14, wherein the thickness of the second-first layer is greater than the thickness of the first-first layer.

17. The secondary battery according to claim 14, wherein the thickness of the first-1 is greater than the thickness of the second-1.

18. The secondary battery of claim 14, wherein the first protective layer further has a first-third thickness at the second overlapping region, the second protective layer further has a second-third thickness at the first overlapping region, and the sum of the first-third thickness and the second-third thickness is greater than the sum of the first-third thickness and the second-third thickness.

19. The secondary battery according to claim 10, wherein the electrode terminals include a first electrode terminal connected to the first electrode and a second electrode terminal connected to the second electrode. The first electrode is a positive electrode, and the second electrode is a negative electrode. The first electrode terminal and the second electrode terminal extend in opposite directions. The protrusions include a first protrusion (1-1) that overlaps with the first electrode contact piece and a first protrusion (1-2) that overlaps with the second electrode contact piece. The protective layer includes a first-1 protective layer on the first-1 protrusion and a first-2 protective layer on the first-2 protrusion, and The thickness of the first-1 protective layer is greater than the thickness of the first-2 protective layer.

20. The secondary battery according to claim 11, wherein the protective layer comprises a first-b protective layer on the first protrusion and a second-b protective layer on the second protrusion, the first-b protective layer and the second-b protective layer extending in different directions.

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