Battery cell and battery cell manufacturing equipment for manufacturing the battery cell

Abstract

A battery cell according to one embodiment of the present invention includes: a battery case, wherein an electrode assembly is installed in a accommodating unit, and the battery case includes a sealing portion, the sealing portion having a structure that seals the periphery; an electrode lead, which is electrically connected to an electrode connector included in the electrode assembly and protrudes outward from the battery case via the sealing portion; and a lead film, which is located at a portion of at least one of an upper portion and a lower portion of the electrode lead corresponding to the sealing portion, wherein a non-adhesive portion is formed on an outer surface of the lead film, and the non-adhesive portion faces the outer surface of the electrode lead.

Description

Technical Field

[0001] This application claims priority to Korean Patent Application No. 10-2021-0030399 filed in Korea on March 8, 2021, the disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates to a battery cell and a battery cell manufacturing apparatus for manufacturing the battery cell, and more particularly, to a battery cell and a battery cell manufacturing apparatus for manufacturing the battery cell that have improved external discharge of gas generated inside the battery cell while ensuring ease of manufacturing. Background Art

[0003] With the development of technology and the increase in demand for mobile devices, the demand for secondary batteries as energy sources is rapidly increasing. In particular, secondary batteries are receiving great attention as energy sources not only for mobile devices such as mobile phones, digital cameras, notebooks, and wearable devices, but also for electric devices such as electric bicycles, electric vehicles, and hybrid vehicles.

[0004] According to the shape of the battery case, these secondary batteries are classified into: cylindrical batteries and square batteries, in which the battery assembly is included in a cylindrical or square metal can; and pouch-type batteries, in which the battery assembly is included in a pouch-type case of an aluminum laminate. Here, the battery assembly included in the battery case is an electric element, which includes a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, and is capable of charging and discharging, and the battery assembly is classified into: a cake roll type, in which a long sheet-type positive electrode and a negative electrode coated with an active material are wound with a separator interposed therebetween; and a stacked type, in which a plurality of positive electrodes and negative electrodes are stacked in sequence with a separator interposed therebetween.

[0005] Among them, in particular, a pouch-type battery including a stacked or stacked / folded type battery assembly in a pouch-type battery case made of an aluminum laminate sheet is increasingly used due to low manufacturing cost, small weight, and easy refitting.

[0006] Figure 1 is a top view showing a conventional battery cell. Figure 2 is along Figure 1 A cross-sectional view taken along the axis a-a'. Figure 1 and Figure 2The conventional battery cell 10 includes a battery case 20 having a receiving portion 21 in which a battery assembly 11 is mounted, and a sealing portion 25 formed by sealing the periphery of the battery case 20. Here, the battery cell 10 includes an electrode lead 30 protruding from the battery case 20 via the sealing portion 25, and a lead film 40 located between the upper and lower portions of the electrode lead 30 and the sealing portion 25.

[0007] However, as the energy density of battery cells has increased in recent years, there is a problem in that the amount of gas generated inside the battery cell has also increased. In the case of a conventional battery cell 10, a component capable of discharging the gas generated inside the battery cell is not included, and therefore, degassing may occur in the battery cell due to the generation of gas. In addition, moisture may penetrate into the battery cell damaged by degassing, which may cause side effects, and there is a problem of battery performance degradation and generation of additional gas. Therefore, there is a growing need to develop a battery cell with improved external discharge of the gas generated inside the battery cell. Summary of the invention

[0008] Technical issues

[0009] The present disclosure is directed to providing a battery cell having improved external discharge of gas generated inside the battery cell while ensuring ease of manufacturing, and a battery cell manufacturing apparatus for manufacturing the battery cell.

[0010] The objectives to be solved by the present disclosure are not limited to the above objectives, and those skilled in the art can clearly understand objectives not mentioned here based on this specification and the drawings.

[0011] Technical Solution

[0012] In one aspect of the present disclosure, a battery cell is provided, comprising: a battery case having a receiving portion and a sealing portion, wherein an electrode assembly is mounted in the receiving portion, the sealing portion being formed by sealing the periphery of the battery case; an electrode lead electrically connected to an electrode connector included in the electrode assembly and protruding out of the battery case via the sealing portion; and a lead film located at a portion corresponding to the sealing portion in at least one of an upper portion and a lower portion of the electrode lead, wherein a non-adhesive portion is formed on an outer surface of the lead film, and the non-adhesive portion is configured to face the outer surface of the electrode lead.

[0013] The non-adhesive portion may extend in a protruding direction of the electrode lead.

[0014] Based on the protruding direction of the electrode lead, one end of the non-adhesive portion may be positioned more inner than an inner surface of the sealing portion, and the other end of the non-adhesive portion may be positioned more outer than an outer surface of the sealing portion.

[0015] An area of ​​one end of the non-adhesive portion positioned more inner than the inner surface of the sealing portion may be smaller than an area of ​​the other end of the non-adhesive portion positioned more outer than the outer surface of the sealing portion.

[0016] The non-adhesive portion may have a circular shape or a rectangular shape.

[0017] The non-adhesive portion may include a first non-adhesive portion and a second non-adhesive portion connected to each other, the first non-adhesive portion may be configured to extend in a longitudinal direction of the non-adhesive portion, and the second non-adhesive portion may be configured to extend in a protruding direction of the electrode lead.

[0018] The length of the first non-adhesive portion may be smaller than the width of the electrode lead, and the length of the second non-adhesive portion may be smaller than the width of the lead film.

[0019] The lead film may include a first lead film and a second lead film, the first lead film may be located at an upper portion of the electrode lead, and the second lead film may be located at a lower portion of the electrode lead.

[0020] The electrode lead may be located between the first lead film and the second lead film, and the first lead film and the second lead film may be integrated with each other.

[0021] The non-adhesive portion may be formed in at least one of the first lead film and the second lead film.

[0022] A surface deformation portion may be formed on the outer surface of the electrode lead, and at least a portion of the surface deformation portion may be configured to face the non-adhesive portion.

[0023] The surface deformation portion may be formed by removing a portion of the outer surface of the electrode lead.

[0024] The surface deformation portion may be configured to extend along a protruding direction of the electrode lead.

[0025] Based on the protruding direction of the electrode lead, one end of the surface deformation portion may be positioned more inward than an inner surface of the sealing portion, and the other end of the surface deformation portion may be positioned more outward than an outer surface of the sealing portion.

[0026] An area of ​​one end of the surface deformation portion positioned more inner than the inner surface of the sealing portion may be smaller than an area of ​​the other end of the surface deformation portion positioned more outer than the outer surface of the sealing portion.

[0027] The surface deformed portion and the non-adhesive portion may have the same shape.

[0028] A coating layer may be formed on the outer surface of the electrode lead, and the surface deformation portion may be formed by removing a portion of the coating layer.

[0029] The coating layer may be made of a metallic material.

[0030] The metal material may include at least one of chromium and nickel.

[0031] The lead film may have a gas permeability of 20 to 60 barrers at 60° C.

[0032] The moisture permeation of the lead film may be 0.02 g to 0.2 g within 10 years under the conditions of 25° C. and 50% RH.

[0033] The lead film may include polypropylene.

[0034] The lead film may have a thickness of 100 μm to 300 μm at the non-adhesive portion.

[0035] A width between the other end of the non-adhesive portion and an outermost end of the lead film may be 2 mm or more.

[0036] In another aspect of the present disclosure, a battery cell manufacturing device for manufacturing the above-mentioned battery cell is also provided, the battery cell manufacturing device including: a clamp configured to press the electrode lead and the lead film together, wherein the clamp includes a recessed portion formed on one surface thereof facing the lead film, the clamp presses the lead film so that the non-adhesive portion is formed at another surface of the lead film opposite to the one surface of the lead film facing the recessed portion, and the non-adhesive portion is formed in the same shape as the shape of the recessed portion.

[0037] The recessed portion may be formed by etching one surface of the jig.

[0038] A surface deformation portion may be formed at the outer surface of the electrode lead, and at least a portion of the surface deformation portion may be formed at a position facing the recessed portion.

[0039] The shape of the surface deformation portion may be the same as the shape of the recessed portion.

[0040] Beneficial Effects

[0041] According to an embodiment, the present disclosure provides a battery cell including a lead film having a non-adhesive portion, and a battery cell manufacturing apparatus for manufacturing the battery cell, thereby improving external discharge of gas generated inside the battery cell while ensuring ease of manufacturing.

[0042] The effects of the present disclosure are not limited to the above effects, and those skilled in the art can clearly understand the effects not mentioned here based on the present specification and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a top view showing a conventional battery cell.

[0044] Figure 2 is along Figure 1 A cross-sectional view taken along the axis a-a'.

[0045] Figure 3 is a top view showing a battery cell according to one embodiment of the present disclosure.

[0046] Figure 4 It is shown that the Figure 3 A three-dimensional view of the electrode leads in a battery cell.

[0047] Figure 5 is along Figure 4 A cross-sectional view taken along the axis c-c'.

[0048] Figure 6 is along Figure 4 A cross-sectional view taken along the axis d-d'.

[0049] Figure 7 It is shown separately Figure 3 An enlarged view of the electrode leads and lead films in a battery cell.

[0050] Figure 8 is along Figure 3 A cross-sectional view taken along the axis b-b'.

[0051] Fig. 9 is a diagram for illustrating a process of bonding an electrode lead and a lead film by a battery cell manufacturing apparatus according to another embodiment of the present disclosure.

[0052] Fig.10 are along Fig. 9 Cross-sectional view taken along axes e-e' and f-f'.

[0053] Fig.11 is with Fig.10A cross-sectional view substantially the same as that of , wherein no surface deformation portion is formed in the electrode lead. DETAILED DESCRIPTION

[0054] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement various embodiments of the present disclosure. The present disclosure can be implemented in various different forms and is not limited to the embodiments described herein.

[0055] In order to clearly explain the present disclosure, parts irrelevant to the description are omitted, and the same or similar components are given the same reference numerals throughout the specification.

[0056] In addition, since the size and thickness of each component shown in the figures are arbitrarily expressed for the convenience of description, the present disclosure is not necessarily limited to the drawings. In order to clearly express the various layers and regions in the figures, the thickness is exaggerated. In addition, in the drawings, for the convenience of explanation, the thickness of some layers and regions is exaggerated.

[0057] Furthermore, throughout the specification, when a part “includes” a certain component, it means that other components may further be included, rather than excluding other components, unless otherwise specified.

[0058] Furthermore, throughout the specification, when a “top view” is mentioned, it means observing a target portion from above, and when a “cross-sectional view” is mentioned, it means a vertically cut cross section observing the target portion from the side.

[0059] Hereinafter, a pouch-shaped battery cell 100 according to one embodiment of the present disclosure will be described. However, here, the description will be based on one of the two side surfaces of the pouch-shaped battery cell 100, but is not necessarily limited thereto, and the same or similar content may be described with the other side surface.

[0060] Figure 3 is a top view showing a battery cell according to one embodiment of the present disclosure.

[0061] refer to Figure 3 , the battery cell 100 according to the present embodiment includes a battery case 200 , an electrode lead 300 , and a lead film 400 .

[0062] The battery case 200 includes: a housing portion 210 in which the electrode assembly 110 is installed; and a sealing portion 250 formed by sealing the periphery of the battery case 200. The sealing portion 250 can be sealed by heat, laser, etc. The battery case 200 can be a laminate including a resin layer and a metal layer. More specifically, the battery case 200 can be made of a laminate, and can include: an outer resin layer forming the outermost layer; a barrier metal layer to prevent material penetration; and an inner resin layer for sealing.

[0063] In addition, the electrode assembly 110 may have a roll-type (wound type), stacked type (laminated type), or composite type (stacked / folded type) structure. More specifically, the electrode assembly 110 may include a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode.

[0064] Hereinafter, the electrode lead 300 and the lead film 400 will be mainly described.

[0065] Figure 4 It is shown that the Figure 3 A three-dimensional view of the electrode leads in a battery cell.

[0066] refer to Figure 3 and Figure 4 , the electrode lead 300 is electrically connected to an electrode tap (not shown) included in the electrode assembly 110, and protrudes outside the battery case 200 via the sealing portion 250. In addition, the lead film 400 is located at a portion corresponding to the sealing portion 250 in at least one of the upper portion and the lower portion of the electrode lead 300. Therefore, the lead film 400 can improve the sealing property of the sealing portion 250 and the electrode lead 300, while preventing a short circuit from occurring in the electrode lead 300 during thermal fusion.

[0067] Figure 5 is along Figure 4 A cross-sectional view taken along the axis c-c'. Figure 6 is along Figure 4 A cross-sectional view taken along the axis d-d'.

[0068] refer to Figure 5 and Figure 6 In this embodiment, a non-adhesive portion 450 is formed on the outer surface of the lead film 400, and the non-adhesive portion 450 may face the outer surface of the electrode lead 300. More specifically, in the lead film 400, the non-adhesive portion 450 may be formed on one surface of the lead film 400 that contacts the electrode lead 300.

[0069] Here, the non-adhesive portion 450 may be formed in a sealing process in which the lead film 400 and the electrode lead 300 are fused to each other. More specifically, the non-adhesive portion 450 may be a portion in which the lead film 400 and the electrode lead 300 are in contact with each other and a relatively small amount of heat and / or pressure is applied to the lead film 400. That is, in the lead film 400, the non-adhesive portion 450 is a portion having a relatively weak adhesive force to the electrode lead 300, and may be a non-adhesive region between the electrode lead 300 and the lead film 400. In other words, the non-adhesive portion 450 is a non-adhesive region between the lead film 400 and the electrode lead 300, which may be used as a gas discharge channel through which gas may flow.

[0070] However, in Figure 5 and Figure 6 , the thickness of the non-adhesive portion 450 is somewhat exaggerated, and actually, the non-adhesive portion 450 may not deform the appearance of the lead film 400 when observed with naked eyes.

[0071] For example, the non-adhesive portion 450 may be a portion where the electrode lead 300 and the lead film 400 contact each other but are not bonded to each other. As another example, the thickness of the non-adhesive portion 450 may be 0.01 μm to several hundred μm. However, the thickness of the non-adhesive portion 450 is not limited thereto, and the non-adhesive portion 450 may have a thickness capable of weakening the adhesive force without damaging the airtightness and durability between the electrode lead 300 and the lead film 400.

[0072] More specifically, the pressure inside the battery cell 100 is higher than the pressure inside the non-adhesive portion 450, and the pressure difference generated thereby can be used as a driving force for the gas. At this time, due to the above-mentioned pressure difference, the gas generated inside the battery cell 100 can be introduced into the non-adhesive portion 450. In addition, due to the gas introduced from the inside of the battery cell 100, the inside of the non-adhesive portion 450 may have a pressure difference with the outside, so the gas introduced into the non-adhesive portion 450 can be discharged to the outside.

[0073] Therefore, in the battery cell 100 according to the present embodiment, the gas generated inside the battery case 200 can be discharged to the non-adhesive part 450 according to the pressure difference with the inside of the non-adhesive part 450, and the gas introduced into the non-adhesive part 450 can be discharged to the outside according to the pressure difference with the outside.

[0074] Furthermore, according to one embodiment of the present disclosure, the degree of gas discharge in the bag and the airtightness and durability of the bag may be adjusted according to the thickness, position, shape, etc. of the non-adhesive portion 450 .

[0075] For example, refer to Figure 5 and Figure 6, the lead film 400 may include a first lead film and a second lead film positioned at the upper portion and the lower portion of the electrode lead 300, respectively. In addition, the first lead film and the second lead film may be integrated with each other. For example, the first lead film and the second lead film may be fused and integrated with each other by means of heat, laser, etc. Therefore, the lead film 400 may improve the sealing properties of the sealing portion 250 and the electrode lead 300 while preventing the side surface of the electrode lead 300 from being exposed to the outside.

[0076] Furthermore, in the lead film 400, as Figure 5 (a) and Figure 6 As shown in (a) of FIG. 1 , the non-adhesive portion 450 may be located in at least one of the first lead film and the second lead film. Figure 5 (b) and Figure 6 As shown in (b), the non-adhesive portion 450 may be located in the first lead film and the second lead film, respectively.

[0077] However, the number of the non-adhesive portions 450 is not limited to the above, and an appropriate number of the non-adhesive portions 450 may be formed for the lead film 400 .

[0078] Therefore, durability and airtightness between the electrode lead 300 and the lead film 400 can be controlled by adjusting the number of non-adhesive portions 450 formed on the lead film 400. In addition, if necessary, by minimizing the number of non-adhesive portions 450, the manufacturing process can be simplified and the cost can be reduced.

[0079] refer to Figure 5 and Figure 6 , the battery cell 100 according to another embodiment of the present disclosure may further include a surface deformation portion 350 formed on the outer surface of the electrode lead 300. Here, at least a portion of the surface deformation portion 350 may face the non-adhesive portion 450. That is, in the electrode lead 300, the surface deformation portion 350 may be formed to have an area equal to or greater than the surface of the non-adhesive portion 450 facing the electrode lead 300.

[0080] Therefore, in the battery cell manufacturing apparatus 1000 ( Fig. 9 ) In the process of forming the non-adhesive portion 450, the portion of the electrode lead 300 forming the surface deformed portion 350 does not contact the non-adhesive portion 450, so it is possible to prevent a portion of the lead film 400 from being pushed into the non-adhesive portion 450. In addition, together with the non-adhesive portion 450, the surface deformed portion 350 can be used as a gas exhaust channel in the battery case 200, so the efficiency of internal gas exhaust can be further improved.

[0081] More specifically, in the electrode lead 300, the surface deformation portion 350 is formed on the outer surface of the electrode lead 300, and the surface deformation portion 350 is located between the lead film 400 and the electrode lead 300. More specifically, in the electrode lead 300, the surface deformation portion 350 may be formed at a position corresponding to the non-adhesive portion 450.

[0082] The surface deformed portion 350 may be formed by removing a portion of the outer surface of the electrode lead 300. Figure 5 and Figure 6 In the figure, the thickness of the surface deformation portion 350 is somewhat exaggerated, and in fact, the thickness of the surface deformation portion 350 can be formed so that the deformation is substantially not observed with the naked eye in the appearance of the electrode lead 300.

[0083] For example, the thickness of the surface deformation portion 350 may be 0.01 μm to several hundred μm. However, the thickness of the surface deformation portion 350 is not limited thereto, and any thickness is applicable as long as it can prevent the lead film 400 from being pushed without damaging the airtightness and durability between the electrode lead 300 and the lead film 400.

[0084] Therefore, during the sealing process in which the sealing portion 250, the electrode lead 300, the lead film 400, etc. are fused, the electrode lead 300 and the lead film 400 are bonded to each other, but since the electrode lead 300 and the lead film 400 are locally separated from each other by means of the surface deformation portion 350, the surface deformation portion 350 can be used together with the non-bonding portion 450 of the lead film 400 as a gas exhaust channel through which gas can flow.

[0085] More specifically, the internal pressure of the battery cell 100 is higher than the internal pressure of the space formed in the surface deformation portion 350 and the non-adhesive portion 450, and the generated pressure difference can be used as a driving force for the gas. At this time, the gas generated inside the battery cell 100 can be introduced into the space formed in the surface deformation portion 350 and the non-adhesive portion 450 by the above-mentioned pressure difference. In addition, due to the gas introduced from the inside of the battery cell 100, the pressure in the space formed in the surface deformation portion 350 and the non-adhesive portion 450 may be different from the external pressure, so the gas introduced into the space formed in the surface deformation portion 350 and the non-adhesive portion 450 can be discharged to the outside.

[0086] In addition, according to one embodiment of the present disclosure, since the phenomenon that the non-adhesive portion 450 is pushed inward is controlled by the thickness, position, shape, etc. of the surface deformation portion 350, the position, size, etc. of the non-adhesive portion 450 can be adjusted. In addition, according to the space formed in the surface deformation portion 350 and the non-adhesive portion 450, the degree of gas discharge in the bag and the airtightness and durability of the bag can be adjusted.

[0087] For example, a coating layer (not shown) may be formed on the outer surface of the electrode lead 300. Here, the coating layer (not shown) may be a layer formed by coating the outer surface of the electrode lead 300. Here, the surface deformation portion 350 may be formed by removing a portion of the coating layer (not shown).

[0088] More specifically, the surface deformation portion 350 may be formed by etching the coating layer (not shown) or the surface of the electrode lead 300 by laser, ultraviolet-ozone (UV-O) treatment, sputtering, etc. However, the etching method is not limited thereto, and any process capable of forming a predetermined shape by processing the surface of the electrode lead 300 may be applied. Here, for ease of description, the coating layer (not shown) is not depicted in the figure, and the outer surfaces of the electrode lead 300 located on both sides of the surface deformation portion 350 may be described as the coating layer (not shown).

[0089] For example, the coating layer (not shown) may be made of a metal material. More specifically, the metal material may include at least one of chromium and nickel. However, the coating layer (not shown) is not limited thereto, and may include a material that is generally coated on the outer surface of the electrode lead 300.

[0090] Therefore, since the surface deformation portion 350 can be formed by removing a coating layer (not shown) formed on the outer surface of the electrode lead 300, there is an advantage in that the surface deformation portion 350 can be prepared by a relatively simple manufacturing process without requiring an additional component. In addition, if the surface deformation portion 350 is formed by removing a coating layer (not shown) formed on the outer surface of the electrode lead 300, it is possible to minimize the deformation of the appearance of the electrode lead 300 when the surface deformation portion 350 is actually observed with the naked eye.

[0091] As another example, the surface deformation portion 350 may be formed by removing a portion of the outer surface of the electrode lead 300. For example, the surface deformation portion 350 may be formed by removing a portion corresponding to the outer surface of the electrode lead 300. That is, the outer surface of the electrode lead 300 may have a stepped structure due to the surface deformation portion 350.

[0092] More specifically, the surface deformation portion 350 may be formed by etching the outer surface of the electrode lead 300 by laser, ultraviolet-ozone (UV-O) treatment, sputtering, etc. However, the etching method of the surface deformation portion 350 is not limited thereto, and any process capable of forming a predetermined shape by processing the surface of the electrode lead 300 may be applied.

[0093] Therefore, since the surface deformation portion 350 may be formed by removing the outer surface of the electrode lead 300 , the surface deformation portion 350 may be prepared through a relatively simple manufacturing process, and has an advantage in that no additional components are required.

[0094] For example, the surface deformation portion 350 may be located on at least one of the upper surface of the electrode lead 300 or the lower surface of the electrode lead 300 based on the surface of the lead film 400 provided with the non-adhesive portion 450. Figure 5 (a) and Figure 6 As shown in (a), when the non-adhesive portion 450 is positioned on the first lead film, the surface deformation portion 350 can be positioned on the upper surface of the electrode lead 300. Conversely, when the non-adhesive portion 450 is positioned on the second lead film, the surface deformation portion 350 can be positioned on the lower surface of the electrode lead 300. In addition, as Figure 5 (b) and Figure 6 As shown in (b), when the non-adhesive portion 450 is positioned on the first lead film and the second lead film, respectively, the surface deformation portion 350 may be located on the upper surface and the lower surface of the electrode lead 300, respectively. However, the number of the surface deformation portions 350 is not limited to the above number, and an appropriate number of surface deformation portions may be formed on the outer surface of the electrode lead 300.

[0095] Therefore, since the number and position of the surface deformation portions 350 can be adjusted to correspond to the non-adhesive portion 450, it is possible to prevent the lead film 400 from being pushed at the non-adhesive portion 450. In addition, the surface deformation portions 350 can be used as a gas exhaust channel together with the non-adhesive portion 450 to effectively increase the amount of gas exhausted from the inside of the battery cell 100.

[0096] Figure 7 It is shown separately Figure 3 An enlarged view of the electrode leads and lead films in a battery cell.

[0097] refer to Figures 5 to 7 , the non-adhesive portion 450 extends along the protruding direction of the electrode lead 300. In other words, based on the protruding direction of the electrode lead 300, the end of the non-adhesive portion 450 located adjacent to the outside of the sealing portion 250 may be positioned further inward than the end of the lead film 400.

[0098] In addition, the width of the non-adhesive portion 450 may be smaller than the width of the lead film 400. In this specification, the width of the non-adhesive portion 450 refers to the maximum value of the distance between one end and the other end of the non-adhesive portion 450 based on the protruding direction of the electrode lead 300, and the width of the lead film 400 refers to the maximum value of the distance between one end and the other end of the lead film 400 based on the protruding direction of the electrode lead 300. In addition, the non-adhesive portion 450 may be positioned between one end and the other end of the lead film 400 based on the protruding direction of the electrode lead 300.

[0099] In addition, the non-adhesive portion 450 extends in a direction perpendicular to the protruding direction of the electrode lead 300, and the length of the non-adhesive portion 450 may be smaller than the width of the electrode lead 300. In this specification, the length of the non-adhesive portion 450 refers to the maximum value of the distance between one end and the other end of the non-adhesive portion 450 based on the direction perpendicular to the protruding direction of the electrode lead 300, and the width of the electrode lead 300 refers to the maximum value of the distance between one end and the other end of the electrode lead 300 based on the direction perpendicular to the protruding direction of the electrode lead 300.

[0100] For example, refer to Figure 7 (a) and (c), the non-adhesive portion 450 may have a circular shape or a rectangular shape. As another example, referring to Figure 7 (b), the non-adhesive portion 450 includes a first non-adhesive portion 450a and a second non-adhesive portion 450b connected to each other. The first non-adhesive portion 450a may extend along the longitudinal direction of the sealing portion 250, and the second non-adhesive portion 450b may extend along the protruding direction of the electrode lead 300. In this specification, the longitudinal direction of the sealing portion 250 refers to a direction perpendicular to the protruding direction of the electrode lead 300.

[0101] Here, the length of the first non-adhesive portion 450a may be smaller than the width of the electrode lead 300, and the length of the second non-adhesive portion 450b may be smaller than the width of the lead film 400. In this specification, the length of the first non-adhesive portion 450a refers to the maximum value of the distance between one end and the other end of the first non-adhesive portion 450a based on a direction perpendicular to the protruding direction of the electrode lead 300, and the length of the second non-adhesive portion 450b refers to the maximum value of the distance between one end and the other end of the second non-adhesive portion 450b based on the protruding direction of the electrode lead 300.

[0102] However, the shape of the non-adhesive portion 450 is not limited to the above-mentioned shape, and the non-adhesive portion 450 may be formed in an appropriate shape on the outer surface of the lead film 400 .

[0103] Therefore, by adjusting the shape of the non-adhesive portion 450 formed on the outer surface of the lead film 400, the durability and airtightness between the electrode lead 300 and the lead film 400 can be controlled. In addition, by changing the shape of the non-adhesive portion 450 as needed, the manufacturing process can be simplified and the cost can be reduced.

[0104] refer to Figures 5 to 7 In another embodiment of the present disclosure, the battery cell 100 may further include a surface deformation portion 350 formed on the outer surface of the electrode lead 300. Here, the surface deformation portion 350 extends along the protruding direction of the electrode lead 300, and based on the protruding direction of the electrode lead 300, the end of the surface deformation portion 350 adjacent to the outer side of the sealing portion 250 may be closer to the inside than the end of the lead film 400. In this specification, the outer side of the sealing portion 250 refers to the end of the sealing portion 250 adjacent to the outside of the battery case 200. In addition, the inner part closer to the inside than the end of the lead film 400 refers to the inner part of the battery case 200 closer to the inside than the end of the lead film 400 adjacent to the outside of the battery case 200.

[0105] More specifically, the width of the surface deformation portion 350 may be smaller than the width of the lead film 400. In this specification, the width of the surface deformation portion 350 refers to the maximum value of the distance between one end and the other end of the surface deformation portion 350 based on the protruding direction of the electrode lead 300. In addition, the surface deformation portion 350 may be positioned between one end and the other end of the lead film 400 based on the protruding direction of the electrode lead 300.

[0106] In addition, the surface deformation portion 350 extends in a direction perpendicular to the protruding direction of the electrode lead 300, and the length of the surface deformation portion 350 may be smaller than the width of the electrode lead 300. In this specification, the length of the surface deformation portion 350 refers to the maximum value of the distance between one end and the other end of the surface deformation portion 350 based on the direction perpendicular to the protruding direction of the electrode lead 300.

[0107] Here, the shape of the surface deformation portion 350 may be the same as or similar to that of the non-adhesive portion 450 .

[0108] For example, refer to Figure 7 (a) and (c), similar to the non-adhesive portion 450, the surface deformation portion 350 may have a circular shape or a rectangular shape. As another example, referring to Figure 7(b), the surface deformation portion 350 includes a first surface deformation portion 350a and a second surface deformation portion 350b connected to each other. The first surface deformation portion 350a may extend in the longitudinal direction of the sealing portion, and the second surface deformation portion 350b may extend in the protruding direction of the electrode lead. Here, the shape of the first surface deformation portion 350a may correspond to the shape of the first non-adhesive portion 450a, and the shape of the second surface deformation portion 350b may correspond to the shape of the second non-adhesive portion 450b.

[0109] For example, the width of the first surface deformation portion 350a may be greater than or equal to the width of the first non-adhesive portion 450a, and the width of the second surface deformation portion 350b may be greater than or equal to the width of the second non-adhesive portion 450b. In the present specification, the width of the first surface deformation portion 350a refers to the maximum value of the distance between one end and the other end of the first surface deformation portion 350a based on the protruding direction of the electrode lead 300, and the width of the first non-adhesive portion 450a refers to the maximum value of the distance between one end and the other end of the first non-adhesive portion 450a based on the protruding direction of the electrode lead 300. The width of the second surface deformation portion 350b refers to the maximum value of the distance between one end and the other end of the second surface deformation portion 350b based on the direction perpendicular to the protruding direction of the electrode lead 300, and the width of the second non-adhesive portion 450b refers to the maximum value of the distance between one end and the other end of the second non-adhesive portion 450b based on the direction perpendicular to the protruding direction of the electrode lead 300.

[0110] However, the shape of the surface deformation portion 350 is not limited to the above shape, and the surface deformation portion 350 may be appropriately formed in a shape corresponding to the non-adhesive portion 450 .

[0111] Therefore, since the shape of the surface deformation portion 350 may be adjusted to correspond to the non-adhesive portion 450 , it is possible to prevent the lead film 400 from being pushed at the non-adhesive portion 450 and effectively increase the amount of gas exhausted from the inside of the battery cell 100 .

[0112] Figure 8 is along Figure 3 A cross-sectional view taken along the axis b-b'.

[0113] refer to Figure 8In one embodiment of the present disclosure, based on the protruding direction of the electrode lead 300, one end of the non-adhesive portion 450 may be positioned more inward than the inner surface of the sealing portion 250, and the other end of the non-adhesive portion 450 may be positioned more outward than the outer surface of the sealing portion 250. In the present specification, the inner surface of the sealing portion 250 refers to the end of the sealing portion 250 adjacent to the inside of the battery case 200, and one end of the non-adhesive portion 450 is positioned more inward than the inner surface of the sealing portion 250 means that one end of the non-adhesive portion 450 is located in a direction more inward of the battery case 200 than the inner surface of the sealing portion 250. If one end of the non-adhesive portion 450 is positioned more inward than the inner surface of the sealing portion 250, the non-adhesive portion 450 is not interfered by the sealing portion 250, and therefore, gas can be more easily introduced into the non-adhesive portion 450. In addition, the outer surface of the sealing portion 250 refers to the end of the sealing portion 250 adjacent to the outside of the battery case 200, and the other end of the non-adhesive portion 450 is positioned more outward than the outer surface of the sealing portion 250 means that the other end of the non-adhesive portion 450 is located in a direction more outward of the battery case 200 than the outer surface of the sealing portion 250. If the other end of the non-adhesive portion 450 is positioned more outward than the outer surface of the sealing portion 250, the gas introduced into the non-adhesive portion 450 can be discharged to the outside more easily. For example, since the other end of the non-adhesive portion 450 is not interfered by the sealing portion 250, the gas introduced into the non-adhesive portion 450 can be discharged to the outside more easily.

[0114] Therefore, the gas generated inside the battery cell 100 can be discharged toward the non-adhesive portion 450, and the gas introduced into the non-adhesive portion 450 can be easily discharged toward the outside. In addition, the amount of gas generated inside the battery cell 100 and discharged to the outside can also be increased.

[0115] In addition, in another embodiment of the present disclosure, the battery cell 100 may further include a surface deformation portion 350 formed on the outer surface of the electrode lead 300. Here, based on the protruding direction of the electrode lead 300, one end of the surface deformation portion 350 may be positioned more inward than the inner surface of the sealing portion 250, and based on the protruding direction of the electrode lead 300, the other end of the surface deformation portion 350 may be positioned more outward than the outer surface of the sealing portion 250. If one end of the surface deformation portion 350 is positioned more inward than the inner surface of the sealing portion 250, the surface deformation portion 350 is not interfered with by the sealing portion 250, and thus, gas can be more easily introduced into the surface deformation portion 350. If the other end of the surface deformation portion 350 is positioned more outward than the outer surface of the sealing portion 250, the gas introduced into the surface deformation portion 350 can be more easily discharged to the outside. For example, since the other end of the surface deformation portion 350 is not interfered with by the sealing portion 250, the gas introduced into the surface deformation portion 350 can be more easily discharged to the outside.

[0116] Therefore, the gas generated inside the battery cell 100 can be discharged toward the surface deformation portion 350 and / or the non-adhesive portion 450, and the gas introduced into the surface deformation portion 350 and / or the non-adhesive portion 450 can be easily discharged toward the outside. In addition, the amount of gas generated inside the battery cell 100 and discharged to the outside can also be increased.

[0117] In addition, since both ends of the surface deformation portion 350 and / or the non-adhesive portion 450 are exposed to the interior of the battery case 200 and the outside of the battery case 200, the gas generated inside the battery case 200 can be easily introduced into the surface deformation portion 350 and / or the non-adhesive portion 450, and can also be more easily discharged to the outside of the surface deformation portion 350 and / or the non-adhesive portion 450.

[0118] Specifically, the gas introduced into the surface deformation portion 350 and / or the non-adhesive portion 450 may be discharged in the Z-axis direction via the lead film 400 on the surface deformation portion 350 and / or the non-adhesive portion 450. For example, if the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 is positioned further outward than the outer surface of the sealing portion 250, the gas introduced into the surface deformation portion 350 and / or the non-adhesive portion 450 may be discharged in the Z-axis direction at a portion of the lead film 400 located between the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 and the outer surface of the sealing portion 250.

[0119] In one embodiment of the present disclosure, the gas permeability of the lead film 400 may be 20 barr to 60 barr, or 30 barr to 40 barr at 60°C. For example, the carbon dioxide permeability of the lead film 400 may satisfy the above range. In addition, based on the thickness of the lead film 400 of 200 μm, the gas permeability at 60°C may satisfy the above range. If the gas permeability of the lead film 400 satisfies the above range, the gas generated inside the battery cell can be discharged more effectively.

[0120] In this specification, the gas permeability may be measured by ASTM F2476-20.

[0121] In one embodiment of the present disclosure, under the conditions of 25° C. and 50% RH, the moisture permeation of the lead film 400 may be 0.02 g to 0.2 g, or 0.02 g to 0.04 g, or 0.06 g, or 0.15 g within 10 years. If the moisture permeation of the lead film 400 satisfies the above range, moisture can be more effectively prevented from penetrating from the lead film 400.

[0122] The moisture permeation amount of the lead film 400 may be measured by adopting the ASTM F 1249 method. At this time, the moisture permeation amount may be measured using equipment officially certified by MCOON.

[0123] In one embodiment of the present disclosure, the gas permeability of the lead film 400 at 60° C. may be 20 to 60 barr, and the moisture permeation amount may be 0.02 g to 0.2 g under the conditions of 25° C. and 50% RH within 10 years. If the gas permeability and moisture permeation amount of the lead film 400 satisfy the above ranges, the gas generated inside the secondary battery can be discharged while more effectively preventing the penetration of moisture from the outside.

[0124] In one embodiment of the present disclosure, the lead film 400 may include a polyolefin-based resin. For example, the lead film 400 may include a polyolefin-based resin that satisfies the above-mentioned gas permeability and / or moisture permeability values. The polyolefin-based resin may include at least one material selected from the group consisting of polypropylene, polyethylene, and polyvinyl difluoride (PVDF). Although the lead film 400 contains polypropylene, the gas permeability of the lead film 400 may be 20 barr to 60 barr at 60°C. In addition, the moisture permeability may be 0.06 grams to 0.15 grams. In this case, the gas generated inside the secondary battery can be discharged more effectively, and moisture can be easily prevented from penetrating from the outside.

[0125] In addition, since the lead film 400 is made of the above-mentioned material, the lead film 400 can maintain the airtightness of the battery cell 100 and prevent leakage of the internal electrolyte.

[0126] refer to Figure 8 , the thickness (H) of the lead film 400 at the non-adhesive portion 450 may be 100 μm to 300 μm, or 100 μm to 200 μm. If the thickness (H) of the lead film 400 at the non-adhesive portion 450 satisfies the above range, the gas inside the battery case 200 can be more easily discharged to the outside.

[0127] refer to Figure 8 , the width (W) between the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 and the outermost end of the lead film 400 may be 2 mm or more, or 2 mm to 3 mm. If the width (W) between the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 and the outermost end of the lead film 400 satisfies the above range, it is easier to prevent the lead film 400 from being torn in the process of discharging the gas generated inside the battery case 200 to the outside.

[0128] In one embodiment of the present disclosure, if one end of the surface deformation portion 350 and / or the non-adhesive portion 450 is positioned more inward than the inner surface of the sealing portion 250, and the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 is positioned more outward than the outer surface of the sealing portion 250, the area of ​​the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 exposed more outward than the outer surface of the sealing portion 250 may be greater than the area of ​​the one end of the surface deformation portion 350 and / or the non-adhesive portion 450 exposed more inward than the inner surface of the sealing portion 250. The gas discharge amount is proportional to the gas discharge area and the pressure. Since the pressure inside the battery case 200 is greater than the pressure outside the battery case 200, if the area of ​​the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 exposed further outward than the outer surface of the sealing portion 250 is greater than the area of ​​one end of the surface deformation portion 350 and / or the non-adhesive portion 450 exposed further inward than the inner surface of the sealing portion 250, the gas generated inside the battery case 200 can be more easily discharged to the outside.

[0129] In one embodiment of the present disclosure, the area of ​​the other end of the surface deformation portion 350 and / or the non-adhesive portion 450 exposed outside the sealing portion 250 may be 40 mm. 2 Up to 80mm 2 This is a size based on the fact that approximately 0.5cc to 3cc of gas can be discharged per day at an internal pressure of 1 atmosphere at 60°C. In addition, this is a size that the amount of moisture permeation can be 0.02g to 0.2g in 10 years under the conditions of 25°C and 50%RH.

[0130] Fig. 9is a diagram for illustrating a process of bonding an electrode lead and a lead film by a battery cell manufacturing apparatus according to another embodiment of the present disclosure. Fig.10 are along Fig. 9 Cross-sectional view taken along axes e-e' and f-f'.

[0131] refer to Fig. 9 and Fig.10 , a battery cell manufacturing apparatus according to another embodiment of the present disclosure is an apparatus for manufacturing a battery cell 100, and includes a jig 1000 for pressing an electrode lead 300 and a lead film 400 together. Therefore, the electrode lead 300 and the lead film 400 may be bonded to each other by heat and / or pressure applied by the jig 1000.

[0132] More specifically, refer to Fig. 9 (a) and Fig.10 In (a), the jig 1000 includes a recessed portion 1050 on one surface facing the lead film 400. Here, the recessed portion 1050 may be formed by etching one surface of the jig 1000.

[0133] For example, the recessed portion 1050 may be formed by etching the outer surface of the jig 1000 by laser, UV-ozone (UVO) treatment, sputtering, etc. However, the etching method is not limited thereto, and any process capable of forming a predetermined shape by processing the surface of the jig 1000 may be applied.

[0134] refer to Fig. 9 (b) and Fig.10 (b), the jig 1000 presses the lead film 400 so that the non-adhesive portion 450 is formed at the other surface of the lead film 400 opposite to the one surface of the lead film 400 facing the recessed portion 1050. Here, the shape of the non-adhesive portion 450 may be formed to be the same as or similar to the shape of the recessed portion 1050.

[0135] In addition, reference Fig. 9 and Fig.10 In another embodiment of the present disclosure, if the surface deformation portion 350 is formed on the outer surface of the electrode lead 300, at least a portion of the surface deformation portion 350 may be formed at a position facing the recessed portion 1050. For example, the shape of the surface deformation portion 350 may be the same as or similar to the shape of the recessed portion 1050. In other words, the shape of the surface deformation portion 350 may be the same as or similar to the shape of the non-adhesive portion 450 formed by the recessed portion 1050.

[0136] Therefore, even if the jig 1000 presses the electrode lead 300 and the lead film 400, the outer surface of the lead film 400 facing the surface deformation portion 350 does not contact the electrode lead 300 via the surface deformation portion 350, and therefore, the non-adhesive portion 450 can be easily formed. In addition, in this case, the lead film 400 can be prevented from being pushed at the non-adhesive portion 450.

[0137] Fig.11 is with Fig.10 A cross-sectional view substantially the same as that of , wherein no surface deformation portion is formed in the electrode lead.

[0138] refer to Fig.11 In one embodiment of the present disclosure, even when the surface deformation portion 350 is not formed on the outer surface of the electrode lead 300, since the heat and / or pressure applied to the outer surface of the lead film 400 corresponding to the recessed portion 1050 is relatively low, the non-adhesive portion 450 can be formed on another surface of the lead film 400 opposite to a surface of the lead film 400 facing the recessed portion 1050.

[0139] Therefore, the non-adhesive portion 450 can be formed on the lead film 400 in the process of fusing the sealing portion 250, the electrode lead 300, and the lead film 400, without requiring a separate additional process for the lead film 400. That is, according to the present embodiment, the manufacturing process is simple, and the amount of gas exhausted from the inside of the battery cell 100 can be effectively increased.

[0140] However, since the electrode lead 300 and the lead film 400 are in contact with each other, a portion of the lead film 400 may be pushed into the non-adhesive portion 450 when the jig 1000 presses the electrode lead 300 and the lead film 400. Fig.11 In (b), since a portion of the lead film 400 is pushed, a protrusion 400 a may be formed in the non-adhesive portion 450 .

[0141] Therefore, in order to prevent the lead film 400 having the protrusion 400a formed in the non-adhesive portion 450 from being pushed and to more effectively increase the amount of gas exhausted from the inside of the battery cell 100, it may be more preferable as follows Fig.10 As shown in FIG. 1 , a surface deformation portion 350 is formed on the outer surface of the electrode lead 300 .

[0142] A battery module according to another embodiment of the present disclosure includes the above-mentioned battery cell. Meanwhile, one or more battery modules according to the present embodiment may be packaged in a battery pack case to form a battery pack.

[0143] The battery module and the battery pack including the battery module can be applied to various devices. These devices can be transportation tools, such as electric bicycles, electric vehicles, hybrid vehicles, etc., but the present disclosure is not limited thereto, and the present disclosure can be applied to various devices that can use the battery module and the battery pack including the battery module, which is also within the scope of the present disclosure.

[0144] Although the preferred embodiments of the present disclosure have been described in detail above, the scope of rights of the present disclosure is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts of the present disclosure defined in the appended claims also fall within the scope of rights of the present disclosure.

Claims

1. A battery cell, the battery cell include: a battery case having a receiving portion in which the electrode assembly is mounted and a sealing portion formed by sealing an outer circumference of the battery case; an electrode lead, the electrode lead being electrically connected to an electrode connector included in the electrode assembly and protruding out of the battery housing via the sealing portion; as well as a lead film located at a portion corresponding to the sealing portion in at least one of an upper portion and a lower portion of the electrode lead, wherein the non-adhesive portion is formed on a surface of the lead film without penetrating the lead film, and the non-adhesive portion is configured to face and contact an outer surface of the electrode lead.

2. The battery cell according to claim 1, in, The non-bonded portion extends in a protruding direction of the electrode lead.

3. The battery cell according to claim 2, in, Based on the protruding direction of the electrode lead, one end of the non-adhesive portion is positioned more inward than an inner surface of the sealing portion, and the other end of the non-adhesive portion is positioned more outward than an outer surface of the sealing portion.

4. The battery cell according to claim 3, in, An area of ​​one end of the non-adhesive portion positioned more inward than the inner surface of the sealing portion is smaller than an area of ​​the other end of the non-adhesive portion positioned more outward than the outer surface of the sealing portion.

5. The battery cell according to claim 1, in, The non-adhesive portion has a circular shape or a rectangular shape.

6. The battery cell according to claim 1, in, The non-adhesive portion includes a first non-adhesive portion and a second non-adhesive portion connected to each other, The first non-adhesive portion is configured to extend in a direction perpendicular to a protruding direction of the electrode lead, and The second non-adhesive portion is configured to extend along the protruding direction of the electrode lead.

7. The battery cell according to claim 6, in, The length of the first non-adhesive portion is smaller than the width of the electrode lead, and The length of the second non-adhesive portion is smaller than the width of the lead film.

8. The battery cell according to claim 1, in, The lead film includes a first lead film and a second lead film, the first lead film is located at an upper portion of the electrode lead, and the second lead film is located at a lower portion of the electrode lead.

9. The battery cell according to claim 8, in, The electrode lead is located between the first lead film and the second lead film, and the first lead film and the second lead film are integrated with each other.

10. The battery cell according to claim 8, in, The non-adhesive portion is formed in at least one of the first lead film and the second lead film.

11. The battery cell according to claim 1, in, A surface deformed portion is formed on the outer surface of the electrode lead, and at least a portion of the surface deformed portion is configured to face the non-adhesive portion.

12. The battery cell according to claim 11, in, The surface deformation portion is formed by removing a portion of the outer surface of the electrode lead.

13. The battery cell according to claim 11, in, The surface deformed portion is configured to extend along a protruding direction of the electrode lead.

14. The battery cell according to claim 13, in, Based on the protruding direction of the electrode lead, one end of the surface deformed portion is positioned more inward than an inner surface of the sealing portion, and the other end of the surface deformed portion is positioned more outward than an outer surface of the sealing portion.

15. The battery cell according to claim 14, in, An area of ​​one end of the surface deformation portion located more inward than the inner surface of the sealing portion is smaller than an area of ​​another end of the surface deformation portion located more outward than the outer surface of the sealing portion.

16. The battery cell according to claim 11, in, The surface deformed portion and the non-adhesive portion have the same shape.

17. The battery cell according to claim 11, in, A coating layer is formed on the outer surface of the electrode lead, and The surface deformation portion is formed by removing a portion of the coating layer.

18. The battery cell according to claim 17, in, The coating layer is made of metal material.

19. The battery cell according to claim 18, in, The metal material includes at least one of chromium and nickel.

20. The battery cell according to claim 1, in, The lead film has a gas permeability at 60° C. of 20 to 60 barrers.

21. The battery cell according to claim 1, in, The moisture permeation of the lead film is 0.02 g to 0.2 g within 10 years under the conditions of 25° C. and 50% RH.

22. The battery cell according to claim 1, in, The lead film includes polypropylene.

23. The battery cell according to claim 1, in, The lead film has a thickness of 100 μm to 300 μm at the non-adhesive portion.

24. The battery cell according to claim 1, in, A width between one end of the non-adhesive portion positioned further outward than an outer surface of the sealing portion and an outermost end of the lead film is 2 mm or more.

25. A battery cell manufacturing apparatus for manufacturing the battery cell according to claim 1, the battery cell manufacturing apparatus include: a clamp configured to press the electrode lead and the lead film together, wherein the jig includes a recessed portion formed on one surface of the jig facing the lead film, The jig presses the lead film so that the non-adhesive portion is formed at the other surface of the lead film opposite to one surface of the lead film facing the recessed portion, and The non-adhesive portion is formed in the same shape as that of the recessed portion.

26. The battery cell manufacturing apparatus according to claim 25, in, The recessed portion is formed by etching one surface of the jig.

27. The battery cell manufacturing apparatus according to claim 25, in, A surface deformation portion is formed at the outer surface of the electrode lead, and at least a portion of the surface deformation portion is formed at a position facing the recessed portion.

28. The battery cell manufacturing apparatus according to claim 27, in, The shape of the surface deformation portion is the same as the shape of the recessed portion.

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