Secondary batteries

Abstract

The present invention relates to a secondary battery and includes an electrode assembly, an outer film having an internal space for housing the electrode assembly and an outer opening that communicates the internal space with the outside, and a cover member that covers the outer opening of the outer film, wherein the cover member may include a first member that closes the outer opening and a second member that extends from the first member and is bonded to the inner surface of the outer film.

Description

Technical Field

[0001] [Cross - Reference to Related Applications] This application claims the benefit of priority based on Korean Patent Application No. 10 - 2023 - 0071156 filed on June 1, 2023 and Korean Patent Application No. 10 - 2024 - 0071969 filed on May 31, 2024, and all the contents disclosed in the Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a secondary battery.

Background Art

[0003] Generally, unlike a primary battery that cannot be charged, a secondary battery means a battery that can be charged and discharged, and is widely used in electronic devices such as mobile phones, notebook computers, camcorders, or electric vehicles. In particular, lithium secondary batteries have a larger capacity and higher energy density than nickel - cadmium batteries or nickel - hydrogen batteries, so their utilization degree has a tendency to increase rapidly.

[0004] Secondary batteries can be classified into cylindrical batteries or prismatic batteries in which an electrode assembly is built into a cylindrical or prismatic metal can according to the form of the battery case, and pouch - type batteries in which the electrode assembly is built into a pouch - type case of a laminate sheet, etc.

[0005] Figure 1 shows an example of a pouch-type secondary battery. The pouch-type secondary battery 1 (pouch cell) includes an electrode assembly 2 formed by alternately stacking electrodes and a separator membrane, and an outer casing material 20 in which the electrode assembly 2 is housed. Electrode tabs 15 may be connected to each electrode of the electrode assembly 2. The electrode tabs 15 may be welded to each other in a predetermined area and then welded to electrode leads 17. The outer casing material 20 includes a housing portion 21 (cup portion) for housing the electrode assembly 2. The housing portion 21 of the outer casing material 20 may be formed in one or two indented sections. Figure 1 illustrates a housing portion 21 formed in two indented sections. Such an outer casing material 20 can be manufactured by molding a pouch film. A sealing portion 23 (terrace portion) is formed around the periphery of the housing portion 21 by sealing.

[0006] On the other hand, the molding depth of the cup portion formed into the pouch film is limited depending on the material properties of the pouch film. This makes it difficult to mold the cup portion deep enough to increase battery capacity, and also necessitates a limited selection of the pouch film material and thickness. As the thickness of the pouch film decreases during the molding of the cup portion, defects such as cracks are more likely to occur in the outer packaging material. Furthermore, the outer packaging material generally includes a pocket portion to collect gases generated during activation, but this pocket portion is removed after the gas is discharged through a degassing process. This results in the problem that a portion of the outer packaging material is always discarded. [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of the present invention is to provide a secondary battery that can solve various problems that arise during the process of molding the cup portion for housing the electrode assembly.

[0008] Furthermore, an object of the present invention is to provide a secondary battery that can prevent the disposal of exterior materials generated after the degassing process. [Means for solving the problem]

[0009] In one example, the secondary battery includes an electrode assembly, an outer film having an internal space for housing the electrode assembly and an outer opening that connects the internal space to the outside, and a cover member that covers the outer opening of the outer film, wherein the cover member may include a first member that closes the outer opening and a second member that extends from the first member and is bonded to the inner surface of the outer film.

[0010] In another example, the outer film may have a shape in which a predetermined sheet having a first end and a second end spaced apart from the first end in a predetermined direction is wound or folded so that the first end and the second end are in contact with each other.

[0011] In yet another example, the inner surface of the first end may be bonded to the inner or outer surface of the second end by adhesion or fusion.

[0012] In yet another example, the second member may be formed along the edge of the first member and extend in a direction that allows viewing the internal space from the first member.

[0013] In yet another example, the cover member may further include a third member formed along the edge of the first member, which together with the second member forms a clamping space in which the end portion of the exterior film adjacent to the opening of the exterior material is sandwiched.

[0014] In yet another example, the third member may, together with the second member, form a C-shaped cross-section that opens toward the exterior film.

[0015] In yet another example, the second member may have a length that allows it to contact the electrode assembly within the outer film.

[0016] In yet another example, the second member may be formed along the edge of the first member and extend outward from the first member.

[0017] In yet another example, the cover member may further include a third member formed along the edge of the second member at the end located on the external side of the second member, which together with the second member forms a clamping space in which the end portion of the exterior film adjacent to the exterior material opening is sandwiched.

[0018] In yet another example, the third member may, together with the second member, form a C-shaped cross-section that opens toward the exterior film.

[0019] In yet another example, the first member may have a through-hole through which an electrode lead electrically connected to the electrode assembly passes.

[0020] In yet another example, the first member may have an electrolyte injection hole for injecting an electrolyte into the internal space of the outer film.

[0021] In yet another example, the second member may be provided to support the portion of the outer film that is joined to the second member, while being supported by the first member when it is joined to the inner surface of the outer film. [Effects of the Invention]

[0022] According to the present invention, since an outer film can be provided without forming a cup portion for housing the electrode assembly, the battery capacity can be easily increased by increasing the size of the outer film, the material and thickness of the outer material sheet for manufacturing the outer film can be selected relatively freely, and defects such as cracks do not easily occur.

[0023] Furthermore, according to the present invention, since electrolyte injection and degassing can be carried out through the electrolyte injection hole in the cover member, unnecessary disposal of the exterior material can be prevented.

[0024] Furthermore, according to the present invention, since the cover member has a space for sandwiching the end portion of the exterior film, the bonding force between the exterior film and the cover member can be increased.

Brief Description of the Drawings

[0025] [Figure 1] It is a diagram showing an example of a pouch-type secondary battery. [Figure 2] It is a perspective view showing a secondary battery according to Example 1 of the present invention. [Figure 3] It is an exploded perspective view of the secondary battery of FIG. 2. [Figure 4] It is a cross-sectional view showing a modified example of the exterior film of FIG. 2. [Figure 5] It is a cross-sectional view taken along line A-A of the secondary battery of FIG. 2. [Figure 6] It is a perspective view showing a secondary battery according to Example 2 of the present invention. [Figure 7] It is an exploded perspective view of the secondary battery of FIG. 6. [Figure 8] It is a cross-sectional view taken along line B-B of the secondary battery of FIG. 6. [Figure 9] It is a perspective view showing a modified example of the secondary battery of FIG. 6. [Figure 10] It is an exploded perspective view of the secondary battery of FIG. 9. [Figure 11] It is a cross-sectional view taken along line C-C of the secondary battery of FIG. 9. [Figure 12] It is a perspective view showing a secondary battery according to Example 3 of the present invention. [Figure 13] It is an exploded perspective view of the secondary battery of FIG. 12. [Figure 14] It is a cross-sectional view taken along line D-D of the secondary battery of FIG. 12. [Figure 15] It is a perspective view showing a modified example of the secondary battery of FIG. 12. [Figure 16] It is an exploded perspective view of the secondary battery of FIG. 15. [Figure 17] It is a cross-sectional view taken along line E-E of the secondary battery of FIG. 15.

Modes for Carrying Out the Invention

[0026] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings, so that those with ordinary skill in the art to which the present invention pertains can easily implement it. However, the present invention may be embodied in a variety of different forms and is not limited to or restricted by the following embodiments.

[0027] In order to clearly explain the present invention, detailed descriptions of prior art that are irrelevant to the description or that may obscure the essence of the invention are omitted. In this specification, when assigning reference numerals to components of each drawing, the same reference numeral is used throughout the specification for identical or similar components.

[0028] Furthermore, the terms and words used in this specification and the claims shall not be interpreted in a manner limited to their ordinary and lexicographical meanings, but rather in a manner consistent with the technical idea of ​​the present invention, in accordance with the principle that inventors themselves may define the concepts of terms as appropriate in order to best describe their invention.

[0029] Example 1 Figure 2 is a perspective view showing a secondary battery 100 according to Embodiment 1 of the present invention, and Figure 3 is an exploded perspective view of the secondary battery 100 of Figure 2. The secondary battery 100 according to Embodiment 1 of the present invention may include an electrode assembly 110, an outer film 130, and a cover member 150, as shown in Figures 2 and 3. The secondary battery 100 of this embodiment will be described below, mainly with reference to Figure 3. For reference, the contents of Embodiment 1 may be similarly applied to other embodiments described later, as long as they do not contradict each other.

[0030] Electrode assembly 110 The electrode assembly 110 may be formed by alternately stacking electrodes and separator films. The electrodes may include a positive electrode and a negative electrode. The electrode assembly 110 may include electrode tabs 111 connected to the electrodes. The electrode tabs 111 may be provided separately or as part of the current collector constituting the electrodes. The electrode tabs 111 may be welded to each other in a predetermined area and then electrically connected to electrode terminals 157, which will be described later.

[0031] Exterior film 130 The outer film 130 may form an internal space 131 for housing the electrode assembly 110. The outer film 130 may form an outer material opening 132 that connects the internal space 131 to the outside of the outer film 130. The outer material opening 132 may be provided at both ends in the longitudinal direction of the outer film 130. The outer material opening 132 may be sealed by a cover member 150, which will be described later.

[0032] The exterior film 130 is obtained from a sheet-type exterior material sheet 130a. The exterior material sheet 130a may be a sheet having a first end 135 and a second end 136 separated from the first end 135 in a predetermined direction. The exterior film 130 is obtained by winding or folding such a sheet 130a so that the first end 135 and the second end 136 are in contact. In this case, the first end 135 and the second end 136 may be joined to each other. Adhesives or heat fusion can be used for joining. In this case, the inner surface of the first end 135 may be joined to the outer surface of the second end 136, as shown in Figure 3. Alternatively, the inner surface of the first end 135' may be joined to the inner surface of the second end 136', as shown in Figure 4. Figure 4 is a cross-sectional view showing a modified example of the exterior film 130 of Figure 2. The joined portion of the first end 135' and the second end 136' may be folded in the direction of the arrow in Figure 4. This reduces the space occupied by the exterior film 130'.

[0033] The exterior material sheet 130a may be a sheet containing a metal layer such as aluminum or stainless steel. The exterior material sheet 130a may be a laminate sheet further containing a resin layer laminated on the metal layer. The exterior material sheet 130a may include a first resin layer disposed on the inner surface of the metal layer. The first resin layer may be a layer formed of polypropylene (PP). The first resin layer may require high insulation and corrosion resistance, but the first resin layer may be formed of other resins that satisfy these requirements. The exterior material sheet 130a may include a second resin layer disposed on the outer surface of the metal layer. The second resin layer may be a layer formed of polyethylene terephthalate (PET). The second resin layer needs to protect the secondary battery 100 while electrically insulating it, and the second resin layer may be formed of other resins that satisfy these requirements.

[0034] Cover member 150 The cover member 150 may be a member that covers the outer material opening 132 of the outer film 130, as shown in Figures 2 and 3. In order to prevent leakage of the electrolyte filling the internal space 131 of the outer film 130, the cover member 150 may seal the outer material opening 132 of the outer film 130. The cover member 150 may seal the outer film 130 simply by being bonded to the outer film 130, or it may seal the outer film 130 by providing a sealant layer (not shown) between the cover member 150 and the outer film 130.

[0035] The cover member 150 may include a first member 151 that closes the exterior material opening 132, as shown in Figures 3 and 5. Figure 5 is a cross-sectional view of the secondary battery of Figure 2 along line AA. The first member 151 may be formed alone or together with a gasket member 156, which will be described later, to completely close the exterior material opening 132. For this purpose, the first member 151 may be formed to correspond to the shape of the exterior material opening 132. In Figure 3, an example of a first member 151 formed in the shape of a rectangle (the shape of the exterior material opening) is shown.

[0036] The first member 151 is made from a material that does not easily allow moisture to pass through, in order to seal the internal space 131 of the outer film 130. For example, the first member 151 may be made from metal or resin, or from a laminate sheet containing a metal layer. This may also be the case for the second member 152, which will be described later.

[0037] The cover member 150 may include a second member 152 extending from the first member 151. The second member 152 may be formed integrally with the first member 151, or it may be formed separately and then joined to the first member 151. The first member 151 and the second member 152 may constitute a cap member that closes the exterior material opening 132.

[0038] The second member 152 may be bonded to the inner surface of the outer film 130 so as to be sealed. Adhesives, heat fusion, or welding can be used for such bonding. For example, heat fusion bonding can be implemented between the resin layer provided on the outer surface of the second member 152 and the resin layer provided on the inner surface of the outer film 130. However, if a gasket member 156 is provided as shown in Figure 5, the second member 152 may be bonded to the outer film 130 via the gasket member 156.

[0039] Conventionally, a cup portion was formed in a pouch film, and the cup portion was sealed with another pouch film to create a pouch-type outer packaging. However, the molding depth of the cup portion was limited by the material properties of the pouch film, making it difficult to mold the cup portion deep enough to increase battery capacity, and the material and thickness of the pouch film also had to be selected in a limited manner. Furthermore, as the thickness of the pouch film decreased during the molding of the cup portion, defects such as cracks were more likely to occur in the pouch-type outer packaging.

[0040] In contrast, in the case of the secondary battery 100 of this embodiment, after providing the outer film 130 without forming the cup portion, the electrode assembly 110 can be inserted into the outer film 130 through the outer material opening 132, and the aforementioned limitations and defects do not occur. Therefore, the battery capacity can be easily increased by increasing the size of the outer film 130, the material and thickness of the outer material sheet 130a can be selected relatively freely, and defects such as cracks may not easily occur. For reference, when forming the outer film 130 by rolling or folding the outer material sheet 130a, the outer material sheet 130a can be rolled or folded with the electrode assembly 110 positioned on the upper surface of the open outer material sheet 130a, and in this case as well, the outer film 130 can be provided without forming the cup portion.

[0041] On the other hand, as shown in Figures 3 and 5, the cover member 150 may include a gasket member 156. The gasket member 156 can prevent leakage of electrolyte between the outer film 130 and the cover member 150. The gasket member 156 may also act as a medium for a firm bond between the outer film 130 and the cover member 150. As shown in Figure 5, the gasket member 156 may be formed to completely enclose the inner and outer surfaces of the second member 152. Alternatively, the gasket member 156 may be formed in the shape of a picture frame to enclose only the outer surface of the second member 152.

[0042] The cover member 150 may include electrode terminals 157. The electrode terminals 157 are configured to electrically connect the secondary battery 100 to another device. The electrode terminals 157 are provided so as to penetrate the first member 151, and the portion exposed to the internal space 131 of the outer film 130 may be connected to electrode tabs 111. The electrode terminals 157 may be formed in an I-shape so as not to be easily detached from the first member 151.

[0043] The first component 151 may include an electrolyte injection hole (not shown) for injecting electrolyte into the internal space 131 of the outer film 130. This allows the electrolyte injection process and the degassing process after activation to proceed. For example, with the secondary battery 100 positioned so that the first component 151 with the electrolyte injection hole is facing upwards, the electrolyte can be injected into the internal space 131 of the outer film 130 through the electrolyte injection hole. In the degassing process, the discharge of internal gas can be guided through the open electrolyte injection hole. After electrolyte injection and degassing, the electrolyte injection hole can be closed by sealing or welding. Alternatively, a valve that can be opened and closed can be installed in the electrolyte injection hole so that the electrolyte injection hole is opened only when necessary.

[0044] Conventionally, pouch-type outer packaging materials consisted of a storage section for housing the electrode assembly and a pocket section for containing gas generated during activation. After the gas in the pocket section was discharged through a degassing process, the pocket section was removed. This resulted in the problem that a portion of the pouch-type outer packaging material was always discarded. However, in this embodiment, the secondary battery 100 can perform electrolyte injection and degassing through an electrolyte injection hole, thus eliminating the need for the aforementioned discarding of outer packaging material.

[0045] On the other hand, the secondary battery of this embodiment is superior not only to conventional pouch-type batteries but also to prismatic batteries. In the case of prismatic batteries, if the volume of the electrode assembly expands during charging and discharging, damage to the electrode assembly may occur due to the prismatic metal can, which hardly changes shape. In contrast, in the secondary battery of this embodiment, if the volume of the electrode assembly expands during charging and discharging, the shape of the outer film changes accordingly, that is, the outer film can be stretched, which has the effect of preventing damage to the electrode assembly.

[0046] Example 2 Figure 6 is a perspective view showing a secondary battery 200 according to Embodiment 2 of the present invention, Figure 7 is an exploded perspective view of the secondary battery 200 of Figure 6, and Figure 8 is a cross-sectional view of the secondary battery 200 of Figure 6 along line BB. The secondary battery 200 according to this embodiment differs from the secondary battery 100 of Embodiment 1 in its cover component, and this will be the main focus of the explanation below. For reference, the contents of Embodiment 2 may also be applied to the embodiments described above and those described later, as long as they do not contradict each other.

[0047] The cover member 250 may include a first member 251 that seals the space between the internal space 131 and the exterior material opening 132, as shown in Figures 6 and 7. The first member 251 is made of a material that does not easily allow moisture to pass through, in order to seal the internal space 131 of the exterior film 130. This may be the same for the second and third members 252 and 255' described later.

[0048] The cover member 250 may include a second member 252 extending from the first member 251. The second member 252 may be bonded to the inner surface of the outer film 130. Adhesives, heat fusion, or welding can be used for such bonding. For example, heat fusion bonding can be implemented between a resin layer provided on the outer surface of the second member 252 and a resin layer provided on the inner surface of the outer film 130.

[0049] On the other hand, as shown in Figure 7, the first member 251 may include a through-hole 253 through which the electrode lead 112, which is electrically connected to the electrode assembly 110, passes. This allows the electrode lead 112 to be easily exposed to the outside when the outer film 130 and the cover member 250 are joined. For example, with the electrode assembly 110 housed in the internal space 131 of the outer film 130, the electrode lead 112 can be easily exposed to the outside by sandwiching it in the through-hole 253 of the first member 251 during the process of joining the cover member 250 to the outer material opening 132 of the outer film 130. For reference, in order to prevent leakage of electrolyte through the through-hole 253, a sealant layer (not shown) may be provided between the outer surface of the electrode lead 112 and the inner surface of the through-hole 253.

[0050] The first member 251 may include an electrolyte injection hole (not shown) for injecting an electrolyte into the internal space 131 of the outer film 130.

[0051] On the other hand, when the second member 252 is bonded to the inner surface of the outer film 130, the second member 252 may be provided to support the portion of the outer film 130 that is bonded to the second member 252, while being supported by the first member 251.

[0052] This will be explained with reference to Figure 8. In order to bond the inner surface of the outer film 130 to the outer surface of the second member 252, it may be necessary to pressurize the outer film 130 toward the second member 252. In such cases, it may be necessary to support the second member 252 during pressurization. In the case of the secondary battery 200 of this embodiment, even if the outer film 130 is pressed toward the second member 252, the first member 251 which is bonded to the second member 252 can support the second member 252, so the second member 252 can be supported during pressurization without using a separate support member. For such support, the first and second members 251 and 252 may be made of a material with higher rigidity than the outer film 130.

[0053] The specific structure of the cover member 250 will be described below. The second member 252 of the cover member 250 may be formed along the edge of the first member 251, as shown in Figure 8. In order to be firmly bonded to the outer film 130, the second member 252 may be formed along the entire periphery of the first member 251, but it may also be considered to be formed along a part of the periphery. Figure 7 illustrates the second member 252 formed along the entire periphery of the first member 251.

[0054] The second member 252 may extend from the first member 251 in the direction of viewing the internal space 131 (to the right in Figure 8). The extension length of the second member 252 can be determined considering the bonding force with the outer film 130. For example, when a strong bond is required, the second member 252 may be made longer to increase the bonding area. The second member 252 may also be set to a length that contacts the electrode assembly 110, as shown in Figure 8. This prevents the electrode assembly 110 from moving inside the outer film 130.

[0055] The cover member 250' may be deformed as shown in Figures 9 to 11. Figure 9 is a perspective view showing a modified example of the secondary battery of Figure 6, Figure 10 is an exploded perspective view of the secondary battery of Figure 9, and Figure 11 is a cross-sectional view of the secondary battery of Figure 9 along the CC line.

[0056] The cover member 250' may include a third member 255' formed along the edge of the first member 251', as shown in Figure 11. The third member 255' may be formed on the entire or a portion of the periphery of the first member 251'. Figure 10 illustrates a third member 255' formed on the entire periphery of the first member 251'.

[0057] The third member 255' may form a clamping space (S; see Figure 10) together with the second member 252'. The clamping space (S) may be a space in which the end portion of the outer film 130 adjacent to the outer material opening 132 is clamped, as shown in Figure 11. When the end portion of the outer film 130 is clamped in the clamping space (S), the bonding force between the outer film 130 and the cover member 250' can be increased. To further increase the bonding force, the clamping space (S) may be filled with adhesive.

[0058] As shown in Figure 11, the third member 255' may form a C-shaped cross section (opening to the right in Figure 11) that opens toward the outer film 130 together with the second member 252'. In Figure 11, the length of the second member 252' is shown to be longer than the length of the third member 255'. As a result, in the process of inserting the end portion of the outer film 130 into the clamping space (S), the end portion can be guided by the second member 252', so that the end portion can be easily inserted into the clamping space (S).

[0059] The third member 255' may include a vertical portion extending perpendicularly from the first member 251' and a horizontal portion extending horizontally from the vertical portion, as shown in Figure 11.

[0060] On the other hand, the first member 251' of this modified example may also be provided with the aforementioned through-hole 253' and electrolyte injection hole (not shown).

[0061] Example 3 Figure 12 is a perspective view showing a secondary battery 300 according to Embodiment 3 of the present invention, Figure 13 is an exploded perspective view of the secondary battery 300 of Figure 12, and Figure 14 is a cross-sectional view of the secondary battery 300 of Figure 12 along the DD line. The secondary battery 300 according to this embodiment differs from the secondary battery 100 of Embodiment 1 in its cover member, and this will be the main focus of the explanation below. For reference, the contents of Embodiment 3 may also be applied to the previously described embodiments, as long as they do not contradict each other.

[0062] The cover member 350 of this embodiment may include a first member 351 and a second member 352, as shown in Figure 13. The first member 351 may be a member that closes the space between the internal space 131 of the outer film 130 and the outer material opening 132. The second member 352 may be formed along the edge of the first member 351 and extend from the first member 351 in a direction toward the outside of the outer film 130 (to the left in Figure 14).

[0063] In order to bond the inner surface of the outer film 130 to the outer surface of the second member 352, it may be necessary to pressurize the outer film 130 toward the second member 352. In such cases, it may be necessary to support the second member 352 during pressurization. In the case of the secondary battery 300 of this embodiment, since the inner surface of the second member 352 is exposed to the outside of the cover member 350, a member for supporting the second member 352 can be easily positioned on the inner surface of the second member 352. For reference, as mentioned above, the second member 352 may be supported by the first member 351.

[0064] The cover member 350' may be deformed as shown in Figures 15 to 17. Figure 15 is a perspective view showing a modified example of the secondary battery of Figure 12, Figure 16 is an exploded perspective view of the secondary battery of Figure 15, and Figure 17 is a cross-sectional view of the secondary battery of Figure 15 along the EE line.

[0065] The cover member 350' may include a third member 355' formed along the edge of the second member 352' at the outer end of the second member 352' (the left end with reference to Figure 17), as shown in Figure 17. The third member 355' may form a clamping space (S; see Figure 16) together with the second member 352' in which the end portion of the outer film 130 adjacent to the outer material opening 132 is clamped. When the end portion of the outer film 130 is clamped in the clamping space (S), the bonding force between the outer film 130 and the cover member 350' can be increased. To further increase the bonding force, the clamping space (S) may be filled with adhesive.

[0066] The third member 355' may, together with the second member 352', form a C-shaped cross section (opening to the right in Figure 17) that opens toward the exterior film 130, as shown in Figure 17. The third member 355' may also include a vertical portion extending perpendicularly from the second member 352' and a horizontal portion extending horizontally from the vertical portion, as shown in Figure 17.

[0067] The above description is merely illustrative of the technical concept of the present invention, and a person with ordinary skill in the art to which the present invention belongs can make various modifications and alterations as long as they do not deviate from the essential characteristics of the present invention.

[0068] Therefore, the embodiments disclosed in this invention are for illustrative purposes only, and not to limit the technical concept of the invention, and the scope of the technical concept of the invention is not limited by such embodiments.

[0069] The scope of protection of this invention shall be interpreted in accordance with the following claims, and all technical ideas within an equivalent scope shall be interpreted as being included within the scope of the rights of this invention. [Explanation of Symbols]

[0070] 1. Pouch-type rechargeable battery 2 electrode assembly 15 Electrode Tabs 17 Electrode Leads 20 Exterior materials 21 Storage Unit 23 Sealing section 100 Secondary battery 110 Electrode assembly 111 Electrode Tabs 112 Electrode Leads 130 Exterior film 130' Exterior Film 130a Exterior material sheet 131 Interior space 132 Exterior material opening 135 First Terminal 135' First terminal 136 Second terminal 136' Second terminal 150 Cover component 151 First Member 152 Second Member 156 Gasket component 157 Electrode terminal 200 Secondary battery 250 Cover component 250' Cover component 251 First Member 251' First Member 252 Second Member 252' Second Member 253 Through Hole 253' Through Hole 255' Third member 300 Secondary battery 350 Cover component 350' Cover component 351 First Member 352 Second Member 352' Second Member 355' Third member

Claims

1. Electrode assembly and An exterior film having an internal space for housing the electrode assembly and an exterior material opening that connects the internal space to the outside, The exterior film includes a cover member that covers the opening of the exterior material, The cover member is A first member that closes the opening in the exterior material, A secondary battery comprising: a second member extending from the first member and bonded to the inner surface of the outer film.

2. The aforementioned exterior film is A secondary battery according to claim 1, wherein a predetermined sheet having a first end and a second end spaced apart from the first end in a predetermined direction is wound or folded such that the first end and the second end are in contact with each other.

3. The inner surface of the first end is The secondary battery according to claim 2, wherein the inner or outer surface of the second end is bonded by adhesion or fusion.

4. The second member is, Formed along the edge of the first member, The secondary battery according to claim 1, which extends from the first member in a direction that views the internal space.

5. The cover member is The secondary battery according to claim 4, further comprising a third member formed along the edge of the first member, which together with the second member forms a clamping space in which the end portion of the outer film adjacent to the outer material opening is clamped.

6. The third member is, The secondary battery according to claim 5, wherein together with the second member, it forms a C-shaped cross section that opens toward the outer film.

7. The secondary battery according to claim 4, wherein the second member has a length that contacts the electrode assembly within the outer film.

8. The second member is, Formed along the edge of the first member, The secondary battery according to claim 1, wherein the first member extends in the direction toward the outside.

9. The cover member is The secondary battery according to claim 8, further comprising a third member formed along the edge of the second member at the end of the second member located on the external side, and together with the second member, forming a clamping space in which the end portion of the outer film adjacent to the outer material opening is clamped.

10. The third member is, The secondary battery according to claim 9, wherein together with the second member, it forms a C-shaped cross section that opens toward the outer film.

11. The first member is, The secondary battery according to claim 1, wherein the electrode assembly has through holes through which electrode leads electrically connected to it pass.

12. The first member is, The secondary battery according to claim 1, further having an electrolyte injection hole for injecting an electrolyte into the internal space of the outer film.

13. The second member is, The secondary battery according to claim 1, wherein, when bonded to the inner surface of the outer film, the first member supports the portion of the outer film that is bonded to the second member.

Images