Secondary batteries

Abstract

This invention relates to a secondary battery that has fewer shape limitations, improved battery capacity, and can reduce the amount of moisture that enters from the outside. The secondary battery according to the present invention includes an electrode assembly, an outer film surrounding a part of the electrode assembly, and a cap surrounding the remaining part of the electrode assembly, wherein the cap includes an outer portion coupled to the outer film, and terminal portions exposed on the outside and inside of the outer portion, respectively, and electrically connected to the electrode assembly at the portion exposed on the inside of the outer portion, the movement of the terminal portion away from the electrode assembly can be restricted by the outer portion.

Description

Technical Field

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0117884 filed on September 5, 2023 and Korean Patent Application No. 10-2024-0066011 filed on May 21, 2024, and all contents disclosed in the documents of said Korean patent application are incorporated as a part of the present specification.

[0002] The present invention relates to a secondary battery, and more particularly, to a secondary battery capable of being charged and discharged.

Background Art

[0003] In recent years, along with the increase in prices of energy sources due to depletion of fossil fuels and growing concern about environmental pollution, demand for environmentally friendly alternative energy sources has become an indispensable factor for future life. Therefore, research on various power generation technologies such as solar power, wind power, tidal power and the like has been continuously conducted, and much attention has also been paid to power storage devices such as batteries for more efficiently utilizing the electric energy produced in this way.

[0004] In addition, as technological development and demand for electronic mobile devices and electric vehicles using batteries increase, the demand for batteries as an energy source has increased sharply, and accordingly, much research has been conducted on batteries that can meet various requirements.

[0005] Batteries that store electrical energy are generally divided into primary batteries and secondary batteries. A primary battery is a disposable consumable battery, whereas a secondary battery is a rechargeable battery manufactured using a material that allows repeated oxidation and reduction processes between electric current and substances. That is, when a reduction reaction of the material occurs caused by electric current, the power source is charged, and when an oxidation reaction of the material occurs, the power source is discharged. Electricity is generated by repeating such charge-discharge cycles.

[0006] Secondary batteries can be classified into cylindrical cells, pouch cells, and prismatic cells, depending on their form. Of these, pouch cells can be manufactured in which an electrode assembly, in which a positive electrode, negative electrode, and separator membrane are stacked inside a pouch, and the outside of the pouch is sealed.

[0007] Conventional pouch cells have a problem where cracks occur in the pouch film during the molding process, resulting in a large amount of pouch film being discarded after the degassing process. Furthermore, the molding depth is limited by the material properties of the pouch film, which in turn limits the increase in battery capacity.

[0008] Therefore, there is a need for a secondary battery that has relatively fewer shape restrictions and improved battery capacity. [Overview of the project] [Problems that the invention aims to solve]

[0009] The object of the present invention is to provide a secondary battery that has fewer shape restrictions, improved battery capacity, and can reduce the amount of moisture that flows in from the outside. [Means for solving the problem]

[0010] The secondary battery according to the present invention includes an electrode assembly, an outer film surrounding a part of the electrode assembly, and a cap surrounding the remaining part of the electrode assembly, wherein the cap includes an outer portion coupled to the outer film, and terminal portions exposed on the outside and inside of the outer portion, respectively, and electrically connected to the electrode assembly at the portion exposed on the inside of the outer portion, and the movement of the terminal portion away from the electrode assembly may be restricted by the outer portion.

[0011] The terminal portion may include an exposed portion that is exposed to the outside of the outer casing, and a support portion that is connected to the exposed portion and supported by the outer casing on the inside of the outer casing to prevent the exposed portion from detaching from the outer casing.

[0012] The exposed portion may include an outer member formed in a shape that overlaps a through hole formed in the outer casing for connecting the exposed portion and the support portion, and positioned on the outside of the outer casing, and a through member formed along the edge of the outer member, extending inward from the edge of the outer member and passing through the through hole.

[0013] The support portion may include a first member that extends from the passing member in a direction perpendicular to the extension direction of the passing member and is provided to be locked to the inner surface of the exterior portion.

[0014] The support portion may further include a second member that extends from the first member toward the electrode assembly and has one end electrically connected to the electrode assembly.

[0015] The second member may include a metal material, and the outer film may include a resin layer bonded to the second member by heat and pressure.

[0016] The exterior portion may include a first cover portion that covers the first member from the outside of the exterior portion, and a second cover portion that is disposed between the second member and the exterior film and bonded to the exterior film, and extends from the first cover portion toward the electrode assembly.

[0017] The support portion may include a metal material, and the first cover portion may include a resin material that is adhesive when heated, and the support portion and the first cover portion may be bonded to each other by heat and pressure.

[0018] The terminal portion may be arranged such that one side protrudes in a direction away from the electrode assembly than one side of the outer casing portion.

[0019] The cap may be arranged such that one surface of the outer casing and one surface of the terminal portion are on the same plane.

[0020] The exterior portion may include a metal material, and the exterior film may include a metal layer bonded to the exterior portion by welding.

[0021] The exterior portion may include a resin material having adhesiveness under heat, and the exterior film may include a resin layer bonded to the exterior portion by heat and pressure.

[0022] The exterior film and the exterior portion may be bonded to each other by an adhesive applied between the exterior film and the exterior portion.

[0023] The exterior portion and the terminal portion may be bonded to each other by an adhesive applied between the exterior portion and the terminal portion.

[0024] The secondary battery according to the present invention includes an electrode assembly, an exterior film having an internal space for accommodating the electrode assembly and an exterior material opening communicating the internal space to the outside, and a cap covering the exterior material opening of the exterior film, wherein the cap includes an exterior portion bonded to the exterior film, and a terminal portion respectively exposed to the outside and the inside of the exterior portion and electrically connected to the electrode assembly at a portion exposed to the inside of the exterior portion, the terminal portion is disposed to close at least a part of the exterior material opening, and may be formed of a material having a lower moisture permeability than a material forming the exterior portion. Effects of the Invention

[0025] The secondary battery according to the preferred embodiment of the present invention does not require a step of molding the exterior film, therefore there are fewer restrictions on the form in which the exterior film accommodates the electrode assembly, the possibility of defects such as cracks occurring in the exterior film is low, and the battery capacity can be improved.

[0026] Furthermore, by reducing the permeation degree of moisture and the like from the outside of the secondary battery into the inside of the secondary battery, the safety of the secondary battery can be improved.

[0027] Furthermore, the structural stability of the secondary battery can be improved depending on the coupling relationship and arrangement form between the terminal portion and the exterior portion.

[0028] The effects of the present invention are not limited to the content exemplified above, and various other effects are included in the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] [Figure 1] It is a perspective view schematically showing the secondary battery according to Embodiment 1 of the present invention. [Figure 2] It is an exploded perspective view schematically showing the secondary battery according to Embodiment 1 of the present invention. [Figure 3] It is a cross-sectional view schematically showing a part of a cross-section of the secondary battery according to Embodiment 1 of the present invention, taken along line A-A' in FIG. 1. [Figure 4] It is an exploded perspective view schematically showing the secondary battery according to Embodiment 2 of the present invention. [Figure 5] It is a cross-sectional view schematically showing a part of a cap and an exterior film of the secondary battery according to Embodiment 2 of the present invention. MODE FOR CARRYING OUT THE INVENTION

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that a person having ordinary knowledge in the technical field to which the present invention pertains can easily carry out the invention. However, the present invention can be implemented in various different forms, and is not restricted or limited to the following embodiments.

[0031] In order to clearly describe the present invention, detailed descriptions of parts unrelated to the description and related known technologies that may obscure the gist of the present invention are omitted. In the present specification, when reference numerals are assigned to components in each drawing, the same or similar reference numerals are assigned to the same or similar components throughout the specification.

[0032] Furthermore, terms and words used in this specification and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather should be interpreted in a manner consistent with the technical concept of the present invention, in accordance with the principle that inventors can appropriately define the concepts of terms in order to best describe their invention.

[0033] Embodiment 1 Figure 1 is a schematic perspective view showing a secondary battery 10 according to Embodiment 1 of the present invention, and Figure 2 is a schematic exploded perspective view showing a secondary battery 10 according to Embodiment 1 of the present invention.

[0034] The secondary battery 10 according to Embodiment 1 of the present invention may include an electrode assembly 100, an outer film 200, and a cap 300. The components of the secondary battery 10 will be described in more detail below. Note that the contents of Embodiment 1 can also be applied to the embodiments described later, unless they conflict with each other.

[0035] The electrode assembly 100 of the secondary battery 10 may include a positive electrode, a negative electrode, and a separator membrane. Here, the separator membrane is placed between the positive electrode and the negative electrode to physically separate them. The electrode assembly 100 may be in a form in which the positive electrode, negative electrode, and separator membrane are stacked, or in a jelly roll form in which the positive electrode, negative electrode, and separator membrane are wound up.

[0036] On the other hand, the electrode assembly 100 may include electrode tabs 110 connected to the electrodes. The electrode tabs 110 may be provided separately or as part of the current collector constituting the electrodes. If the electrode assembly 100 is an all-solid-state battery, a solid electrolyte may be provided instead of a separator membrane.

[0037] Referring to Figure 2, the secondary battery 10 according to Embodiment 1 of the present invention may include an outer film 200. The outer film 200 of the secondary battery 10 may be provided so as to surround a part of the electrode assembly 100. Specifically, the outer film 200 may be provided so as to surround the cap 300 and the electrode assembly 100, which will be described later. More specifically, the outer film 200 may be coupled with the cap 300 to form an internal space, and the electrode assembly 100 may be housed in the internal space.

[0038] The outer casing film 200 of the secondary battery 10 may have a shape in which a sheet or film is wound along the side surface of the electrode assembly 100. That is, the outer casing film 200 may be arranged in a manner that surrounds the side of the electrode assembly 100. Here, one end and the other end of the outer casing film 200 may be in contact with each other to surround the electrode assembly 100. In relation to the manner in which one end and the other end of the outer casing film 200 are in contact with each other, it is possible that one surface of one end and the other surface of the other end are joined in contact with each other (see Figure 2), or that one surface of one end and the other surface of the other end are joined in contact with each other (see Figure 4). These are merely examples, and there are various ways in which one end and the other end of the outer casing film 200 are joined to form a space for housing the electrode assembly 100.

[0039] In relation to the method by which one end of the outer film 200 is joined to the other, the two ends of the outer film 200 may be joined to each other by heat sealing or by heat and pressure sealing. That is, the outer film 200 may contain a substance that has heat sealing properties. Specifically, the outer film 200 may contain a substance that melts and adheres when heated. For example, the outer film 200 may contain one or more substances selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, poly(p-phenylenebenzobisoxazole), polyarylate, Teflon®, and glass fiber. Polyolefin resins such as polypropylene (PP) or polyethylene (PE) are mainly used. In particular, polypropylene (PP) has excellent mechanical properties such as tensile strength, rigidity, surface hardness, abrasion resistance, and heat resistance, as well as chemical properties such as corrosion resistance.

[0040] Alternatively, the outer film 200 may be arranged so that it surrounds a portion of the electrode assembly 100, and the cap 300 surrounds the rest of the electrode assembly 100. Specifically, when the outer film 200 is arranged so as to surround the electrode assembly 100 along its side surface, outer openings may be formed at both ends of the electrode assembly 100. The cap 300 of the secondary battery 10 may be connected to the outer film 200 in such a way that it covers the outer openings at both ends of the electrode assembly 100, and the electrode assembly 100 may be housed in the internal space formed by the outer film 200 and the cap 300.

[0041] As an example of a method of joining the cap 300 and the outer film 200, the cap 300 and the outer film 200 may be joined by welding. Specifically, the outer part 310 may include a metal material, and the outer film 200 may include a metal layer in the portion facing the outer part 310 that is joined to the outer part 310 by welding.

[0042] Another example of a method of bonding the cap 300 and the outer film 200 is that the cap 300 and the outer film 200 may be bonded by a seal. Specifically, the outer part 310 may include a resin material that is heat-adhesive, and the outer film 200 may include a resin layer in the portion facing the outer part 310 that is bonded to the outer part 310 by heat and pressure. Here, the resin layer may include the aforementioned heat-sealing material.

[0043] Conventional pouch cells were constructed by molding a sheet or film to form a cup portion for housing the electrode assembly 100. During the molding process of the cup portion, the depth that could be molded was limited by the material properties of the sheet or film, and this also limited the capacity that could house the electrode assembly 100. Furthermore, when molding a sheet or film, the thickness was thinnest at the corners, resulting in frequent defects such as cracks. In addition, conventional pouch cells required a gas collection section to collect gas in the degassing process to remove gas accumulated inside the pouch, and a large amount of the gas collection section was removed and discarded after the degassing process.

[0044] In contrast, the secondary battery 10 according to Embodiment 1 of the present invention allows the outer film 200 to be used in accordance with the volume of the electrode assembly 100, thus eliminating any limitations on the capacity that can accommodate the electrode assembly 100. Furthermore, since molding of the cup portion is not required, defects such as cracks in the outer film 200 can be prevented, and the material and thickness of the outer film 200 can be selected relatively freely. At the same time, since the electrolyte injection and degassing processes can be performed using the cap 300, no discarded outer film 200 is generated, improving the economic efficiency of the process.

[0045] On the other hand, although not described in detail in this invention, the cap 300 may further include an electrolyte inlet for injecting the electrolyte, a gas outlet for discharging gas during the degassing process, and so on.

[0046] Figure 3 is a schematic cross-sectional view showing a portion of the cross-section of a secondary battery 10 according to Embodiment 1 of the present invention, cut along line A-A' in Figure 1. Referring to Figure 3, the cap 300 of the secondary battery 10 according to Embodiment 1 of the present invention may include an outer casing 310 and a terminal portion 320.

[0047] The outer casing 310 of the cap 300 may be coupled to the outer film 200. The terminal portion 320 of the cap 300 may also be coupled to the outer casing 310 and provided to be exposed on the outside and inside of the outer casing 310, respectively. Here, the inside of the outer casing 310 can mean a part of the internal space formed by the cap 300 and the outer film 200, and the outside of the outer casing 310 can mean the outer space of the cap 300 and the outer film 200. On the other hand, the portion of the terminal portion 320 that is exposed on the inside of the outer casing 310 may be electrically connected to the electrode assembly 100. Here, the electrical connection includes both a direct connection between the terminal portion 320 and the electrode assembly 100 and an indirect connection mediated by other electrically conductive members.

[0048] On the other hand, as an example of a method of joining the outer casing 310 and the terminal portion 320, joining by sealing is possible. The terminal portion 320 may include a metal material, and the outer casing 310 may include a resin material that becomes adhesive when heated. In this case, the resin material of the outer casing 310 that becomes adhesive when heated melts and is joined to the terminal portion 320 by pressure.

[0049] As an example of a configuration to improve the structural stability of the cap 300, the terminal portion 320 of the cap 300 according to Embodiment 1 of the present invention may be restricted by the outer casing portion 310 from moving away from the electrode assembly 100. In connection with this, the terminal portion 320 of the cap 300 may include an exposed portion 322 and a support portion 321.

[0050] The exposed portion 322 of the terminal portion 320 may be provided so as to be exposed to the outside of the outer casing portion 310. Therefore, the terminal portion 320, which is electrically connected to the electrode assembly 100, can make electrical contact with the outside via the exposed portion 322 provided so as to be exposed to the outside of the outer casing portion 310. In other words, the secondary battery 10 can provide electrical energy to the outside via the exposed portion 322.

[0051] Referring to Figure 3, the exposed portion 322 of the terminal portion 320 may include the outer member 3221 and the passing member 3222.

[0052] The outer member 3221 of the exposed portion 322 may be positioned outside the outer casing 310. That is, one surface of the exposed portion 322 may be positioned to protrude away from the electrode assembly 100 (upward in Figure 3) from one surface of the outer casing 310. Using Figure 3 as a reference, one surface of the exposed portion 322 may be the upper surface of the exposed portion 322, and one surface of the outer casing 310 may be the upper surface of the outer casing 310.

[0053] In relation to the more specific shape of the outer member 3221, the exterior portion 310 may have a through hole for connecting the exposed portion 322 and the support portion 321, and the outer member 3221 may be formed in a shape that overlaps the through hole of the exterior portion 310. Overlap can mean that the entire outer member 3221 is positioned within the through hole H, based on a projection from the outside of the exterior portion 310 toward the inside of the exterior portion 310 (downward in Figure 3). Such a shape allows the outer member 3221 to be inserted into the through hole H from the inside of the exterior portion 310 toward the outside of the exterior portion 310 (upward in Figure 3).

[0054] The through member 3222 of the exposed portion 322 may extend from the edge of the outer member 3221 in the inward direction of the outer casing portion 310 (downward in Figure 3) and pass through the through hole. Preferably, the through member 3222 is formed along the edge of the outer member 3221.

[0055] The support portion 321 of the terminal portion 320 may be connected to the exposed portion 322 and supported by the outer casing 310 inside the outer casing 310 to prevent the exposed portion 322 from detaching from the outer casing 310. Since the support portion 321 is supported by the outer casing 310, the cap 300 has improved structural stability.

[0056] In relation to the shape of the support portion 321 supported by the exterior portion 310, the support portion 321 may include a first member 3211 and a second member 3212.

[0057] The first member 3211 of the support portion 321 may extend from the passing member 3222 in a direction perpendicular to the extension direction of the passing member 3222 (the vertical direction in Figure 3) (the left-right direction in Figure 3). Here, the first member 3211 may be provided so as to be locked to the inner surface of the exterior portion 310. Using Figure 3 as a reference, the inner surface of the exterior portion 310 can mean the lower surface of the exterior portion 310.

[0058] The second member 3212 of the support portion 321 extends from the first member 3211 toward the electrode assembly 100, and one end may be electrically connected to the electrode assembly 100. Here, the second member 3212 may consist of multiple members. That is, the support portion 321 may be electrically connected to the electrode assembly 100 at multiple positions. Therefore, if the secondary battery 10 includes multiple electrode assemblies 100, each of the multiple electrode assemblies 100 may be electrically connected to a second member 3212 located in close proximity to it. This allows the secondary battery 10 to efficiently increase its battery capacity.

[0059] As shown in Figure 2, the second member 3212 of the support portion 321 may be formed along the edge of the first member 3211. This is just one example, and the second member 3212 of the support portion 321 may be connected only to the opposing side corners of the first member 3211, which has a substantially rectangular cross-section. That is, the second member 3212 may be connected only to the upper and lower parts of the first member 3211 with reference to Figure 2. Here, the second member 3212 extending from the upper and lower parts of the first member 3211 may be connected to two electrode tabs 110 positioned vertically, respectively.

[0060] On the other hand, the second member 3212 may be bonded to the outer film 200. Specifically, the second member 3212 may include a metal material, and the outer film 200 may include a resin layer with thermal adhesion in the portion facing the second member 3212. Thus, the second member 3212 and the outer film 200 can be bonded together by heat and pressure sealing.

[0061] In the cap 300 of the secondary battery 10 according to Embodiment 1 of the present invention, the outer casing 310 and the terminal portion 320 may cover the electrode assembly 100. Depending on the material of the outer casing 310, moisture on the outside of the outer casing 310 may permeate through the outer casing 310 and penetrate to the inside. Moisture penetration can cause malfunctions in the secondary battery 10. In the cap 300 of the secondary battery 10 according to Embodiment 1 of the present invention, the terminal portion 320, which is made of metal, covers the electrode assembly 100 together with the outer casing 310, thereby reducing the area of ​​the outer casing 310 that moisture can penetrate. Also, since the support portion 321 is arranged in a manner that it is supported by the outer casing 310, the moisture penetration path formed between the support portion 321 and the outer casing 310 becomes longer. Therefore, the secondary battery 10 according to Embodiment 1 of the present invention can reduce the amount of moisture that penetrates into the interior, thereby reducing the phenomenon of problems occurring in the performance of the secondary battery 10.

[0062] As an example of a configuration to reduce moisture penetration, in the secondary battery 10 according to Embodiment 1 of the present invention, the terminal portion 320 of the cap 300 may contain a material with relatively low moisture permeability. Specifically, the terminal portion 320 of the cap 300 may be made of a material with lower moisture permeability than the material constituting the outer casing 310. Therefore, by having both the outer casing 310 and the terminal portion 320 cover the electrode assembly 100, the amount of moisture that permeates into the space containing the electrode assembly 100 can be reduced compared to the case where only the outer casing 310 covers the electrode assembly 100.

[0063] Embodiment 2 Figure 4 is a schematic exploded perspective view showing a secondary battery 10' according to Embodiment 2 of the present invention, and Figure 5 is a schematic cross-sectional view showing a portion of the cap 300 and outer film 200 of the secondary battery 10' according to Embodiment 2 of the present invention.

[0064] Hereinafter, a detailed explanation of the configuration identical to that of the secondary battery 10 according to Embodiment 1 of the present invention will be omitted, and the differences will be explained in detail. The secondary battery 10' according to Embodiment 2 of the present invention differs from the secondary battery 10 according to Embodiment 1 in the form of the outer casing 310', the arrangement of the terminals 320, and the method of coupling the configuration.

[0065] Referring to Figure 4, the secondary battery 10' according to Embodiment 2 of the present invention may include an electrode assembly 100, an outer film 200, and a cap 300. The outer film 200 of the secondary battery 10' may be provided so as to surround a part of the electrode assembly 100. Specifically, the outer film 200 may be provided so as to surround the cap 300 and the electrode assembly 100. More specifically, the outer film 200 may be coupled with the cap 300 to form an internal space, in which the electrode assembly 100 may be housed.

[0066] As an example of a configuration to improve the coupling force with the terminal portion 320, the outer casing portion 310' of the cap 300 according to Embodiment 2 of the present invention may include a first cover portion 311 and a second cover portion 312.

[0067] Referring to Figure 5, the first cover portion 311 may be provided so as to cover the first member 3211 from the outside of the outer casing portion 310'. The second cover portion 312 may extend from the first cover portion 311 toward the electrode assembly 100. Specifically, the second cover portion 312 may be positioned between the second member 3212 and the outer casing film 200. More specifically, the second cover portion 312 may be formed along the edge of the first cover portion 311.

[0068] The second cover portion 312 may be positioned between the second member 3212 and the outer film 200, with one side bonded to the second member 3212 of the support portion 321 and the other side bonded to the outer film 200. Here, adhesive 400 may be applied to bond the second cover portion 312 to the other components. That is, adhesive 400 may be applied to one side and the other side of the second cover portion 312. The second cover portion 312 may be bonded to the second member 3212 and the outer film 200 by adhesive 400. Preferably, adhesive 400 is applied between the outer film 200 and the outer portion 310' to bond the outer film 200 and the outer portion 310' to each other, and adhesive 400 is applied between the outer portion 310' and the terminal portion 320 to bond the outer portion 310' and the terminal portion 320 to each other. Here, there are various types and application forms of adhesive 400 for bonding.

[0069] On the other hand, in the cap 300 according to Embodiment 2 of the present invention, one surface of the terminal portion 320 may be arranged on the same plane as one surface of the outer casing portion 310'. In that case, since there is no portion of the terminal portion 320 that protrudes to the outside of the outer casing portion 310', the arrangement of multiple secondary batteries 10' can be made easier.

[0070] The secondary battery according to the embodiments of the present invention described above can effectively prevent performance degradation due to changes in the volume of the electrode assembly. More specifically, the electrode assembly may undergo volume changes (expansion or contraction) during the charging and discharging process.

[0071] In this embodiment, the secondary battery is surrounded by an outer film having predetermined flexibility and stretchability, so that the outer film can be stretched or folded in accordance with changes in the volume of the electrode assembly. As a result, in this embodiment, the electrode assembly is not subjected to further deformation due to excessive friction or force, and thus a decrease in the performance of the secondary battery due to such deformation can be effectively prevented.

[0072] In contrast, in a secondary battery (e.g., a prismatic secondary battery) in which an electrode assembly is housed in a cylindrical metal or plastic housing with a predetermined rigidity, the volume inside the housing is fixed. As a result, if the volume of the electrode assembly changes during the charging and discharging process, stress and friction may occur between the inner wall of the housing and the electrode assembly. This can lead to deformation (e.g., strain) of the electrode assembly, which can result in a decrease in the performance of the secondary battery.

[0073] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible within the equivalent scope of the technical concept and the appended claims by persons with ordinary skill in the art to which the present invention pertains. [Explanation of symbols]

[0074] 10, 10' secondary battery 100 electrode assembly 110 Electrode Tabs 200 Exterior Film 300 caps 310, 310' Exterior part 311 First Cover Section 312 Second Cover Section 320 Terminal section 321 Support part 322 Exposed part 400 Adhesives 3211 First Member 3212 Second Member 3221 Outer member 3222 Passing member

Claims

1. Electrode assembly and An outer film surrounding a part of the electrode assembly, The electrode assembly includes a cap that surrounds the remaining portion of the electrode assembly, The aforementioned cap is The exterior portion is bonded to the aforementioned exterior film, The exterior portion includes terminal portions that are exposed on the outer and inner sides, respectively, and that are electrically connected to the electrode assembly at the portion exposed on the inner side of the exterior portion. The aforementioned terminal portion is A secondary battery in which movement away from the electrode assembly is restricted by the outer casing.

2. The aforementioned terminal portion is The exposed portion that is exposed to the outside of the exterior part, The secondary battery according to claim 1, further comprising a support portion connected to the exposed portion and supported by the outer casing on the inside of the outer casing to prevent the exposed portion from detaching from the outer casing.

3. The exposed portion is, An outer member is formed in a shape that overlaps the through hole formed in the outer casing for connecting the exposed portion and the support portion, and is positioned on the outside of the outer casing; The secondary battery according to claim 2, further comprising a through member formed along the edge of the outer member, extending inward from the edge of the outer member to the outer casing, and passing through the through hole.

4. The aforementioned support portion is The secondary battery according to claim 3, further comprising a first member that extends from the passing member in a direction perpendicular to the extension direction of the passing member and is provided to be locked to the inner surface of the outer casing.

5. The aforementioned support portion is The secondary battery according to claim 4, further comprising a second member extending from the first member toward the electrode assembly, with one end electrically connected to the electrode assembly.

6. The aforementioned second member includes a metal material, The secondary battery according to claim 5, wherein the outer film includes a resin layer bonded to the second member by heat and pressure.

7. The aforementioned exterior part is, A first cover portion covers the first member from the outside of the exterior portion, The secondary battery according to claim 5, comprising a second cover portion disposed between the second member and the outer film and bonded to the outer film, and extending from the first cover portion toward the electrode assembly.

8. The support portion includes a metal material, The first cover portion includes a resin material that is adhesive when heated. The secondary battery according to claim 7, wherein the support portion and the first cover portion are bonded to each other by heat and pressure.

9. The aforementioned terminal portion is The secondary battery according to claim 1, wherein one surface is arranged to protrude in a direction away from the electrode assembly from one surface of the exterior part.

10. The aforementioned cap is The secondary battery according to claim 1, wherein one surface of the exterior portion and one surface of the terminal portion are arranged on the same plane.

11. The exterior part includes a metal material, The secondary battery according to claim 1, wherein the outer film includes a metal layer that is welded to the outer part.

12. The exterior part includes a resin material that adheres with heat, The secondary battery according to claim 1, wherein the outer film includes a resin layer bonded to the outer part by heat and pressure.

13. The secondary battery according to claim 1, wherein the outer film and the outer part are bonded to each other by an adhesive applied between the outer film and the outer part.

14. The secondary battery according to claim 1, wherein the exterior part and the terminal part are bonded to each other by an adhesive applied between the exterior part and the terminal part.

15. Electrode assembly and An exterior film having an internal space for housing the electrode assembly and an exterior material opening that communicates the internal space with the outside, The exterior film includes a cap that covers the opening of the exterior material, The aforementioned cap is The exterior portion is bonded to the aforementioned exterior film, The exterior portion includes terminal portions that are exposed on the outer and inner sides, respectively, and that are electrically connected to the electrode assembly at the portion exposed on the inner side of the exterior portion. The aforementioned terminal portion is A secondary battery, which is positioned to close at least a portion of the opening in the exterior material and is made of a material with lower moisture permeability than the material constituting the exterior part.

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