Battery cell comprising insulating film having function of preventing short circuit due to condensate, and battery module comprising same

Abstract

The present invention relates to a battery cell and a battery module comprising the same, the battery cell comprising an insulating film having a function of preventing a short circuit due to condensate, the battery cell comprising: a pouch case; an electrode assembly stored in the pouch case and including a negative electrode, a positive electrode, and a separator interposed between the negative electrode and the positive electrode; a pair of electrode leads composed of a negative electrode lead and a positive electrode lead; and a pair of insulating films composed of a negative electrode insulating film and a positive electrode insulating film, the negative electrode insulating film being interposed between the inner side of the pouch case sealing portion and the negative electrode lead, and the positive electrode insulating film being interposed between the inner side of the pouch case sealing portion and the positive electrode lead, the negative electrode insulating film and / or the positive electrode insulating film includes a non-overlapping portion exposed outside the pouch case sealing portion, and the non-overlapping portion includes a flow path configured to allow condensate to move therethrough.

Description

Technical Field

[0001] This application claims the benefit of priority to Korean Patent Application No. 2022-0177032, filed on December 16, 2022, the disclosure of which is incorporated herein by reference in its entirety.

[0002] The present invention relates to a battery cell having an insulating film having a function of preventing a short circuit due to condensate and a battery module including the battery cell, and more particularly, to a battery cell having an insulating film having a function of preventing a short circuit due to condensate and a battery module including the battery cell, the battery cell being configured so that a flow channel, a waterproof coating, or a barrier tape is formed at the insulating film disposed between a bag case and an electrode lead, thereby significantly reducing the probability of a short circuit due to condensate. Background Art

[0003] With the recent development of alternative energy due to air pollution and energy depletion caused by the use of fossil fuels, the demand for secondary batteries capable of storing generated electrical energy has increased. Secondary batteries capable of charging and discharging are closely used in daily life. For example, secondary batteries are used in mobile devices, electric vehicles, and hybrid electric vehicles.

[0004] Due to the increase in the use of mobile devices, the increase in the complexity of mobile devices, and the development of electric vehicles, the required capacity of lithium secondary batteries used as energy sources for various electronic devices inevitably used in modern society has increased. In order to meet the needs of users, a plurality of battery cells are provided in small devices, and a battery module including a plurality of battery cells electrically connected to each other or a battery pack including a plurality of battery modules is used in vehicles, etc.

[0005] In addition, due to the temperature difference between the inside and outside of the battery module or battery pack during use, condensation may occur in the battery module or battery pack. Condensation is a phenomenon in which moisture contained in the air forms droplets on the surface of an object when the temperature of the moisture-containing air drops to the dew point or lower, and such condensate is mainly generated when the temperature in the secondary battery is lower than the ambient temperature.

[0006] The condensate thus generated may cause the secondary cell to operate abnormally. For example, when condensation occurs in a pouch-shaped battery cell, an electrical short circuit may occur due to capillary action between the pouch case including the metal layer and the electrode lead, which may shorten the life of the battery cell or may cause a fire.

[0007] In this regard, a secondary battery having an insulating film configured to prevent condensate flow is disclosed in Prior Art Document 1. Figure 1As shown in the figure, the insulating film 40 is exposed to the outside of the joining interface 11 between the electrode leads 20 and 30 and the bag sheath 10, and a concave depression 41 configured to prevent a short circuit due to condensate is formed in the side surface and upper surface of the portion of the insulating film that does not overlap with the electrode leads 20 and 30.

[0008] When using an insulating film having concave depressions formed therein, as in Prior Art Document 1, short circuits can be prevented to a certain extent; however, since the concave depressions are formed only in portions of the edges of the insulating film, the risk of short circuits due to condensate is still high.

[0009] In particular, when battery cells are vertically assembled into a battery module or a battery pack, the generated condensate may easily move to the electrode leads.

[0010] (Prior art literature)

[0011] (Prior Art Document 1) Korean Patent Application Publication No. 2013-0036991 Summary of the invention

[0012] Technical issues

[0013] The present invention has been made in view of the above problems, and an object of the present invention is to provide a battery cell having an insulating film with a function of preventing a short circuit due to condensate, and a battery module including the battery cell, which can reliably prevent condensate generated outside a battery cell case from moving to an electrode lead.

[0014] Technical Solution

[0015] A battery cell according to the present invention for achieving the above purpose comprises: a bag shell 100, the bag shell being made of a laminated sheet and having a housing space; an electrode assembly 200, the electrode assembly being housed in the bag shell 100, the electrode assembly comprising a negative electrode 210 provided with a negative electrode connector 211, a positive electrode 220 provided with a positive electrode connector 221, and a separator 230 interposed between the negative electrode 210 and the positive electrode 220; a pair of electrode leads 300, the pair of electrode leads comprising a negative electrode lead 310 electrically connected to the negative electrode connector 211 and a positive electrode lead 230 electrically connected to the positive electrode connector 221. 320; and a pair of insulating films 400, the pair of insulating films being composed of a negative insulating film 410 and a positive insulating film 420, the negative insulating film being interposed between the inner surface of the sealed portion of the bag shell 100 and the negative lead 310, and the positive insulating film being interposed between the inner surface of the sealed portion of the bag shell 100 and the positive lead 320, wherein the negative insulating film 410 and / or the positive insulating film 420 are provided with a non-overlapping portion exposed outside the sealed portion of the bag shell 100, and the non-overlapping portion is provided with a flow channel configured to allow condensate to move therethrough.

[0016] In addition, in the battery cell according to the present invention, the negative electrode non-overlapping portion 412 of the negative electrode insulating film 410 may be provided with a first flow channel 412a, which is configured to allow condensate to move therethrough in a direction orthogonal to the negative electrode lead 310, and the positive electrode non-overlapping portion 422 of the positive electrode insulating film 420 may be provided with a third flow channel 422a, which is configured to allow condensate to move therethrough in a direction orthogonal to the positive electrode lead 320.

[0017] In addition, in the battery cell according to the present invention, the cross-sectional shape of each of the first flow channel 412a and the third flow channel 422a may be hemispherical, triangular, or quadrilateral, and opposite ends of each of the first flow channel and the third flow channel may be open.

[0018] In addition, in the battery cell according to the present invention, the negative electrode non-overlapping portion 412 may further be provided with a second flow channel 412 b parallel to the first flow channel 412 a and spaced apart by a predetermined distance.

[0019] In addition, the first flow channel 412a and the second flow channel 412b may have different cross-sectional areas.

[0020] In addition, in the battery cell according to the present invention, the positive electrode non-overlapping portion 422 may further be provided with a fourth flow channel 422 b parallel to the third flow channel 422 a and spaced apart by a predetermined distance.

[0021] In addition, in the battery cell according to the present invention, the third flow channel 422a and the fourth flow channel 422b may have different cross-sectional areas.

[0022] In addition, in the battery cell according to the present invention, the negative electrode non-overlapping portion 412 may be provided with a first waterproof coating 412c formed not to overlap with the first flow channel 412a, and the positive electrode non-overlapping portion 422 may be provided with a second waterproof coating 422c formed not to overlap with the third flow channel 422a.

[0023] In addition, in the battery cell according to the present invention, the first waterproof coating 412 c may be provided along an edge in a direction orthogonal to the negative electrode lead 310 , and the second waterproof coating 422 c may be provided along an edge in a direction orthogonal to the positive electrode lead 320 .

[0024] In addition, in the battery cell according to the present invention, the negative electrode non-overlapping portion 412 may be provided with a first barrier tape 412 d formed along an edge in a direction orthogonal to the negative electrode lead 310 .

[0025] In addition, in the battery cell according to the present invention, the positive electrode non-overlapping portion 422 may be provided with a second barrier tape 422 d formed along an edge in a direction orthogonal to the positive electrode lead 320 .

[0026] In addition, the present invention provides a battery module including a battery cell.

[0027] In addition, a method for manufacturing a battery cell according to the present invention includes the following steps: a first step of preparing a bag shell 100 having a storage space configured to store an electrode assembly 200; a second step of attaching a negative electrode insulating film 410 and a positive electrode insulating film 420 to a negative electrode lead 310 and a positive electrode lead 320 electrically connected to the electrode assembly 200, respectively; and a third step of storing the electrode assembly 200 in the storage space of the bag shell 100 and sealing the edge of the bag shell 100, wherein the negative electrode insulating film 410 and / or the positive electrode insulating film 420 are attached to the negative electrode lead 310 and the positive electrode lead 320 electrically connected to the electrode assembly 200, respectively. The positive electrode insulating film 420 is provided with a non-overlapping portion exposed outside the sealing portion of the bag shell 100, the negative electrode non-overlapping portion 412 of the negative electrode insulating film 410 is provided with a first flow channel 412a, which is configured to allow condensate to move therethrough in a direction orthogonal to the negative electrode lead 310, and the positive electrode non-overlapping portion 422 of the positive electrode insulating film 420 is provided with a third flow channel 422a, which is configured to allow condensate to move therethrough in a direction orthogonal to the positive electrode lead 320.

[0028] Beneficial Effects

[0029] It is clear from the above description that the battery cell having an insulating film with a function of preventing short circuits due to condensate and the battery module including the battery cell according to the present invention have the advantage that the non-overlapping portion of the insulating film exposed outside the bag shell is provided with a flow channel, which is configured to allow condensate to move therethrough in a direction orthogonal to the electrode lead, thereby significantly reducing the probability of short circuits due to condensate.

[0030] In addition, the battery cell having an insulating film with a function of preventing short circuits due to condensation and the battery module including the battery cell according to the present invention have the advantage that a waterproof coating is formed on the non-overlapping portion of the insulating film exposed outside the bag shell, thereby significantly reducing the probability of short circuits due to condensation.

[0031] In addition, the battery cell having an insulating film with a function of preventing short circuits due to condensate and the battery module including the battery cell according to the present invention have the advantage that the non-overlapping portion of the insulating film exposed outside the bag shell is provided with a barrier tape, thereby significantly reducing the probability of short circuits due to condensate. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a plan view of a battery cell having a conventional insulating film configured to prevent condensate flow.

[0033] Figure 2 is an exploded perspective view of a battery cell according to a first preferred embodiment of the present invention.

[0034] Figure 3 is a diagram showing an insulating film disposed on Figure 2 FIG. 1 is a plan view showing a state of an electrode lead of an electrode assembly.

[0035] Figure 4 It is along Figure 3 A cross-sectional view taken along line AA.

[0036] Figure 5 is a plan view showing a state in which an insulating film according to a second preferred embodiment of the present invention is mounted on an electrode lead of an electrode assembly.

[0037] Figure 6 It is along Figure 5 A cross-sectional view taken along line BB.

[0038] Figure 7 is a plan view showing a state in which an insulating film according to a third preferred embodiment of the present invention is mounted on an electrode lead of an electrode assembly.

[0039] Figure 8 It is along Figure 7 Cross-sectional view taken along line CC.

[0040] Fig. 9 is a plan view showing a state in which an insulating film according to a fourth preferred embodiment of the present invention is mounted on an electrode lead of an electrode assembly.

[0041] Fig.10 It is along Fig. 9 A cross-sectional view taken along line DD in FIG.

[0042] Fig.11 is a perspective view of a battery module accommodating a battery cell according to the present invention.

[0043] Fig.12 is a flow chart illustrating a method for manufacturing a battery cell according to the present invention. DETAILED DESCRIPTION

[0044] Now, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the preferred embodiments of the present invention. However, when describing in detail the operating principle of the preferred embodiments of the present invention, when the detailed description of the known functions and configurations incorporated herein will make the subject matter of the present invention unclear, the detailed description will be omitted.

[0045] In addition, the same reference numerals will be used throughout the drawings to represent components that perform similar functions or operations. Where a component is referred to as being connected to another component throughout the specification, not only may the component be directly connected to the other component, but the component may also be indirectly connected to the other component via other components. In addition, unless otherwise specified, the inclusion of a particular element does not mean that other elements are not included, but rather means that such elements may also be included.

[0046] Hereinafter, a battery cell having an insulating film with a function of preventing a short circuit due to condensate and a battery module including the battery cell according to the present invention will be described with reference to the accompanying drawings.

[0047] Figure 2 is an exploded perspective view of a battery cell according to a first preferred embodiment of the present invention, Figure 3 is a diagram showing an insulating film disposed on Figure 2 A plan view of the electrode lead of the electrode assembly is shown in FIG. Figure 4 It is along Figure 3 A cross-sectional view taken along line AA.

[0048] like Figures 2 to 4 As shown in , the battery cell according to the present invention includes a pouch case 100 , an electrode assembly 200 , an electrode lead 300 , and an insulating film 400 .

[0049] First, the pouch case 100 may be composed of a lower case and an upper case, and a pouch-shaped accommodation space configured to accommodate the electrode assembly 200 is formed in the pouch case.

[0050] The bag case 100 is made of a laminated sheet including an outer resin layer 110 , a metal layer 120 , and an inner resin layer 130 so as to form a receiving portion therein.

[0051] Specifically, the outer resin layer 110 located at the outermost side of the pouch case 100 may be made of a heat-resistant polymer that exhibits excellent tensile strength, moisture permeation resistance, and air permeability so as to ensure heat resistance and chemical resistance while protecting the electrode assembly 200. As an example, the outer resin layer may be made of nylon or polyethylene terephthalate; however, the present invention is not limited thereto.

[0052] The metal layer 120 located between the outer resin layer 110 and the inner resin layer 130 corresponds to a barrier layer configured to prevent moisture or various gases from penetrating into the battery. As a preferred material of the metal layer 120, an aluminum thin film that is lightweight and easily formable may be used.

[0053] The inner resin layer 130 located at the innermost side of the bag shell 100 is arranged to be in direct contact with the electrode assembly 200, so the inner resin layer must exhibit high insulation properties and high electrolyte resistance. In addition, the inner resin layer must exhibit high sealing properties so as to hermetically seal the bag shell with the outside, that is, the thermally bonded sealing portion between the inner resin layers must exhibit excellent thermal bonding strength.

[0054] The inner resin layer 130 may be made of a material selected from polyolefin resins such as polypropylene, polyethylene, polyethylene acrylate, or polybutylene, polyurethane resins, and polyimide resins exhibiting excellent chemical resistance and high sealing properties. However, the present invention is not limited thereto, and it is most preferred to use polypropylene, which exhibits excellent mechanical properties (such as tensile strength, rigidity, surface hardness, and impact resistance) and excellent chemical resistance.

[0055] Despite Figure 2 The middle accommodation space is shown to be provided in each of the upper case and the lower case, but the accommodation space may be provided in only one of the upper case and the lower case.

[0056] Next, the electrode assembly 200 will be described. The electrode assembly 200 placed in the accommodation space of the pouch case 100 may be a roll-type battery assembly configured to have a structure in which a long sheet-type negative electrode 210 and a long sheet-type positive electrode 220 are wound so that a separator 230 is interposed therebetween, a stacked-type electrode assembly configured to have a structure in which a rectangular negative electrode 210 and a rectangular positive electrode 220 are stacked with a separator 230 interposed therebetween, a stacked-type electrode assembly configured to have a structure in which a unit cell is wound using a long separation film, a stacked-type electrode assembly configured to have a state in which unit cells are stacked with separators interposed therebetween and then attached to each other; however, the present invention is not limited thereto.

[0057] Specifically, the negative electrode 210 is manufactured by applying a slurry mixture of a negative active material and a binder to a negative current collector.

[0058] As the negative electrode active material, for example, carbon such as non-graphitizable carbon or graphite-like carbon; such as Li x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1), Sn x Me 1-x Me' y O zMetal composite oxides such as (Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, Group I, II, and III elements in the periodic table, halogens; 0 < x ≤ 1; 1 ≤ y ≤ 3; 1 ≤ z ≤ 8); lithium metal; lithium alloys; silicon-based alloys; tin-based alloys; metal oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, or Bi2O5; conductive polymers such as polyacetylene; Li-Co-Ni-based materials; or Si-based materials such as Si, SiO, SiO2, or mixtures thereof; however, the present invention is not limited thereto.

[0059] The positive electrode 220 is manufactured by applying a slurry mixture of the positive electrode active material and the binder to the positive electrode current collector.

[0060] The positive electrode active material may be composed of, for example, layered compounds such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2) or compounds substituted with one or more transition metals; lithium magnesium oxide represented by the chemical formula Li 1+x Mn 2- x O4 (where x = 0 to 0.33) or lithium manganese oxides such as LiMnO3, LiMn2O3, and LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, or Cu2V2O7; Ni-site type lithium nickel oxides represented by the chemical formula LiNi 1-x M x O2 (where M = Co, Mn, Al, Cu, Fe, Mg, B, or Ga, and x = 0.01 to 0.3); lithium manganese composite oxides represented by the chemical formula LiMn 2-x M x O2 (where M = Co, Ni, Fe, Cr, Zn, or Ta, and x = 0.01 to 0.1) or the chemical formula Li2Mn3MO8 (where M = Fe, Co, Ni, Cu, or Zn); LiMn2O4 in which a part of Li in the chemical formula is substituted with alkaline earth metal ions; disulfides; or Fe2(MoO4)3; however, the present invention is not limited thereto.

[0061] On the other hand, each of the negative electrode current collector and the positive electrode current collector includes a portion to which a slurry including the active material is applied and an uncoated portion to which the slurry is not applied. The uncoated portion is cut or a separate conductive member is connected to the uncoated portion by ultrasonic welding to form a pair of electrode joints, that is, the negative electrode joint 221 and the positive electrode joint 231.

[0062] A thin insulating film having high ion permeability and mechanical strength is used as the separator 230, which is interposed between the negative electrode 210 and the positive electrode 220 or disposed outside the negative electrode 210. The pore size of the separator 230 is generally 0.01 μm to 10 μm, and the thickness of the separator is generally 5 μm to 300 μm. A sheet or non-woven fabric made of a chemically resistant and hydrophobic olefin polymer such as polypropylene, glass fiber, or polyethylene may be used as the separator 230; however, the present invention is not limited thereto.

[0063] The negative electrode lead 310 and the positive electrode lead 320 constituting a pair of electrode leads 300 are electrically connected to the negative electrode tab 211 and the positive electrode tab 221 , respectively, and are exposed to the outside of the pouch case 100 .

[0064] Here, a pair of electrode leads 300 and a pair of electrode connectors can be electrically connected to each other by welding (e.g., ultrasonic welding). The connection by ultrasonic welding is performed according to the following principle: high-frequency vibration generated by ultrasonic waves of about 20kHz is applied, and due to the friction at the interface between the electrode connector and the electrode lead due to the operation of the horn and the anvil, the vibration energy is converted into heat energy, thereby quickly performing welding. Of course, welding is not limited to ultrasonic welding, as long as the connector bundle and the lead can be electrically connected to each other by welding.

[0065] Although not shown in the drawings, a protective tape (not shown) may be provided at a portion where the electrode tab and the electrode lead overlap each other to wrap the overlapped portion.

[0066] Since the electrode tab and the electrode lead are connected to each other by welding, surfaces of the electrode tab and the electrode lead may not be smooth, resulting in poor insulation.

[0067] In other words, if the weld surface is not smooth, when the weld and the bag housing contact each other due to impact, the inner resin layer is peeled off, whereby the metal layer is exposed, resulting in poor insulation. Therefore, in order to prevent poor insulation, it is preferred to wrap the weld with a protective tape.

[0068] Here, the protective tape can be made of an insulating material. As an example, the protective tape can be made of polypropylene, polyethylene, polyester fiber or polyimide. However, the present invention is not limited thereto, as long as the material can wrap the weld and keep insulation when in contact with the bag housing.

[0069] Next, the insulating film 400 will be described. The insulating film 400 is provided at the sealing portion of the bag case 100, that is, at a position where the edge of the bag case 100 to be sealed for sealing and the electrode lead 300 overlap each other. The reason for this is that the insulating film 400 can maintain the sealing of the bag case 100 while preventing the power generated by the electrode assembly 200 from flowing to the bag case 100 via the electrode lead 300.

[0070] Specifically, in order to prevent the bag case 100 from directly contacting the negative lead 310, the negative electrode insulating film 410 includes a negative electrode overlapping portion 411 located at a portion where the negative electrode lead 310 and the sealed portion of the bag case 100 overlap with each other, and a negative electrode non-overlapping portion 412 exposed outside the sealed portion of the bag case 100.

[0071] In addition, in order to prevent direct contact between the bag shell 100 and the positive lead 320, the positive electrode insulating film 420 may include a positive electrode overlapping portion 421 located at the portion where the positive lead 320 and the sealed portion of the bag shell 100 overlap with each other, and a positive electrode non-overlapping portion 412 exposed outside the sealed portion of the bag shell 100.

[0072] In this case, it is preferred that the negative non-overlapping portion 412 or the positive non-overlapping portion 412 is provided with a flow channel configured to guide the condensate flow in a desired direction, and it is more preferred that the negative non-overlapping portion 412 is provided with a first flow channel 412a and the positive non-overlapping portion 422 is provided with a third flow channel 422a.

[0073] Here, the first flow channel 412a of the negative electrode non-overlapping portion 412 is formed in a direction orthogonal to the negative electrode lead 310, and the third flow channel 422a of the positive electrode non-overlapping portion 422 is formed in a direction orthogonal to the positive electrode lead 320, so as to guide the condensate to flow downward along the flow channel while suppressing the condensate from moving in a direction toward the lead when the battery cell is mounted in a vertical direction.

[0074] In the present invention, the flow channel corresponds to a long passage configured so that the generated condensate is directly introduced into the flow channel and moves therethrough, or the movement of the condensate is guided by capillary action. Therefore, the cross-sectional shape of each of the first flow channel 412a and the third flow channel 422a is not particularly limited as long as the flow direction of the condensate can be determined. For example, the cross-sectional shape of the flow channel may be hemispherical, triangular, or quadrilateral, and the width and depth of the flow channel may be tens of nanometers (nm) to several micrometers (μm).

[0075] Preferably, the opposite ends of each of the first flow channel 412a and the third flow channel 422a are open so that the generated condensate is introduced into the first flow channel 412a and the third flow channel 422a and then discharged from the first flow channel and the third flow channel or flows in contact with the flow channel.

[0076] It is preferred that the lead film 400 is made of a non-conductive material that conducts electricity poorly, and generally uses an insulating tape that is easily attached to the electrode lead and has a relatively small thickness; however, the present invention is not limited thereto.

[0077] Specifically, the lead film can be made of at least one material selected from the group consisting of polyimide (PI), polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polyvinyl chloride (PVC), high-density polyethylene (HDPE) and epoxy resin, and can be bonded to the inner resin layer of the bag shell by hot melting using heat and pressure.

[0078] Figure 5 is a plan view showing a state in which an insulating film according to a second preferred embodiment of the present invention is disposed on an electrode lead of an electrode assembly, and Figure 6 It is along Figure 5 A cross-sectional view taken along line BB.

[0079] The second embodiment is the same as the first embodiment except for the insulating film, and thus only the insulating film will be described hereinafter.

[0080] In the second embodiment of the present invention, a plurality of flow channels are formed in each of the negative electrode non-overlapping portion 412 and the positive electrode non-overlapping portion 422 .

[0081] The case where two flow channels are provided will be described by way of example. The negative non-overlapping portion 412 of the negative electrode insulating film 410 is provided with a first flow channel 412a and a second flow channel 412b. In this case, it is preferred that the first flow channel 412a and the second flow channel 412b are parallel to each other and spaced apart by a predetermined distance, and it is more preferred that the cross-sectional area of ​​the first flow channel 412a located at the relatively inner side is larger than the cross-sectional area of ​​the second flow channel 412b located at the edge, so as to minimize the movement of the condensate to the negative electrode lead 310.

[0082] In addition, the positive non-overlapping portion 422 of the positive electrode insulating film 420 is provided with a third flow channel 422a and a fourth flow channel 422b, and their positions and cross-sectional areas are the same as the positions and cross-sectional areas of the first flow channel 412a and the second flow channel 412b of the negative non-overlapping portion 412, so the repeated description will be omitted.

[0083] Figure 7is a plan view showing a state in which an insulating film according to a third preferred embodiment of the present invention is disposed on an electrode lead of an electrode assembly, and Figure 8 It is along Figure 7 Cross-sectional view taken along line CC.

[0084] The third embodiment is the same as the first embodiment except for the insulating film, and thus only the insulating film will be described hereinafter.

[0085] In the third embodiment of the present invention, a water-repellent coating is further formed on each of the negative electrode non-overlapping portion 412 and the positive electrode non-overlapping portion 422 .

[0086] Specifically, it is preferred that the negative electrode non-overlapping portion 412 is provided with a first waterproof coating 412 c formed not to overlap with the first flow channel 412 a , and it is more preferred that the first waterproof coating 412 c is provided along an edge in a direction orthogonal to the negative electrode lead 310 .

[0087] When the first waterproof coating layer 412 c is formed on the negative electrode non-overlapping portion 412 as described above, condensate can be more reliably prevented from flowing toward the negative electrode lead 310 .

[0088] Similarly, it is preferred that the positive electrode non-overlapping portion 422 is provided with a second waterproof coating 422c formed not to overlap with the third flow channel 422a, and it is more preferred that the second waterproof coating 422c is provided along the edge in a direction orthogonal to the positive electrode lead 320.

[0089] Here, a known water-repellent material such as a fluorine-based compound or a silane-based compound may be used as the water-repellent coating material, and the coating may be formed using a dipping method or a spraying method.

[0090] Although the case where the water-repellent coating is formed on the non-overlapping portion having a single flow channel has been described in the third embodiment, the water-repellent coating may be formed on the non-overlapping portion having two or more flow channels as in the second embodiment.

[0091] Fig. 9 is a plan view showing a state in which an insulating film according to a fourth preferred embodiment of the present invention is disposed on an electrode lead of an electrode assembly, and Fig.10 It is along Fig. 9 A cross-sectional view taken along line DD in FIG.

[0092] The fourth embodiment is the same as the first embodiment except for the insulating film, and thus only the insulating film will be described hereinafter.

[0093] In the fourth embodiment of the present invention, a barrier tape is further formed on each of the negative electrode non-overlapping portion 412 and the positive electrode non-overlapping portion 422 .

[0094] Specifically, the negative non-overlapping portion 412 is provided with a first barrier tape 412 d formed along an edge in a direction orthogonal to the negative lead 310 , and the positive non-overlapping portion 422 is provided with a second barrier tape 422 d formed along an edge in a direction orthogonal to the positive lead 320 .

[0095] When the first barrier tape 412 d is disposed at the negative electrode non-overlapping portion 412 and the second barrier tape 422 d is disposed at the positive electrode non-overlapping portion 422 as described above, a step is formed, which may help prevent condensation from flowing toward the negative electrode lead 310 and the positive electrode lead 320 .

[0096] Although the case where the barrier tape is formed on the non-overlapping portion having a single flow channel has been described in the fourth embodiment, the barrier tape may be formed on the non-overlapping portion having two or more flow channels as in the second embodiment.

[0097] Fig.11 is a perspective view of a battery module in which a battery cell according to the present invention is housed. Fig.11 As shown in FIG. 2 , the battery module 2000 is configured such that a plurality of battery cells 1000 are accommodated in a module case 2100 having an accommodation space.

[0098] In this case, as described in the first to fourth embodiments, each battery cell 1000 is a battery cell having at least one of a barrier tape, a waterproof coating, and a flow channel arranged at an insulating film, and the battery cells are accommodated in a state of standing side by side in a direction perpendicular to the bottom surface of the module housing 2100.

[0099] Even if condensation occurs due to temperature changes, etc., the generated condensate flows downward due to the barrier tape, waterproof coating or flow channel provided at the insulating film, thereby preventing a short circuit due to the condensate. Although not shown in the figure, the module housing 2100 may also be provided with a passage configured to discharge the condensate that has flowed downward to the outside.

[0100] Fig.12 is a flow chart illustrating a battery cell manufacturing method according to the present invention. The battery cell manufacturing method according to the present invention may include: a first step of preparing a pouch case having a housing space configured to house an electrode assembly, a second step of attaching a negative electrode insulating film and a positive electrode insulating film to a negative electrode lead and a positive electrode lead electrically connected to the electrode assembly, respectively, and a third step of housing the electrode assembly in the housing space of the pouch case and sealing the edge of the pouch case.

[0101] In addition, before attaching the insulating film to the electrode lead, it is preferred to pre-form at least one of a flow channel, a waterproof coating and a barrier tape at the non-overlapping portion of each of the negative electrode insulating film and the positive electrode insulating film, that is, at the portion exposed outside the sealing portion of the bag shell, and it is more preferred to form the flow channel, the waterproof coating and the barrier tape in a direction orthogonal to the electrode lead.

[0102] The present invention provides a battery pack including a battery module.

[0103] Those skilled in the art to which the present invention pertains will appreciate that various applications and modifications are possible within the category of the present invention based on the above description.

[0104] (Description of Reference Numerals)

[0105] 1000: Battery cells

[0106] 100: Bag shell

[0107] 110: Outer resin layer

[0108] 120: Metal layer

[0109] 130: Inner resin layer

[0110] 200: Electrode assembly

[0111] 210: Negative electrode 211: Negative electrode connector

[0112] 220: Positive electrode 221: Positive electrode connector

[0113] 230: Diaphragm

[0114] 300: Electrode lead

[0115] 310: Negative lead

[0116] 320: Positive lead

[0117] 400: Insulation film

[0118] 410: Negative electrode insulation film

[0119] 411: Negative electrode overlap

[0120] 412: Negative non-overlapping part

[0121] 412a: first flow channel 412b: second flow channel

[0122] 412c: first waterproof coating 412d: first barrier tape

[0123] 420: Positive electrode insulation film

[0124] 421: Positive electrode overlap

[0125] 422: Positive non-overlapping part

[0126] 422a: third flow channel 422b: fourth flow channel

[0127] 422c: Second waterproof coating 422d: Second barrier tape

[0128] 2000: Battery Module

[0129] 2100: Module housing

Claims

1. A battery cell, comprising: A bag housing, the bag housing being made of a laminated sheet and having a containing space; an electrode assembly, the electrode assembly being accommodated in the pouch case, the electrode assembly comprising a negative electrode provided with a negative electrode terminal, a positive electrode provided with a positive electrode terminal, and a separator interposed between the negative electrode and the positive electrode; a pair of electrode leads, the pair of electrode leads consisting of a negative electrode lead electrically connected to the negative electrode tab and a positive electrode lead electrically connected to the positive electrode tab; and a pair of insulating films, the pair of insulating films consisting of a negative electrode insulating film and a positive electrode insulating film, the negative electrode insulating film being interposed between the inner surface of the sealed portion of the bag case and the negative electrode lead, and the positive electrode insulating film being interposed between the inner surface of the sealed portion of the bag case and the positive electrode lead, wherein the negative electrode insulating film and / or the positive electrode insulating film is provided with a non-overlapping portion exposed outside the sealing portion of the bag housing, and The non-overlapping portions are provided with flow channels configured to allow condensate to move therethrough.

2. The battery cell according to claim 1, wherein: the negative electrode non-overlapping portion of the negative electrode insulating film is provided with a first flow channel configured to allow condensate to move therethrough in a direction orthogonal to the negative electrode lead, and The positive electrode non-overlapping portion of the positive electrode insulating film is provided with a third flow channel configured to allow condensate to move therethrough in a direction orthogonal to the positive electrode lead.

3. The battery cell according to claim 2, wherein: Each of the first flow channel and the third flow channel has a hemispherical cross-section, and Opposite ends of each of the first flow channel and the third flow channel are open.

4. The battery cell according to claim 2, wherein: The negative electrode non-overlapping portion is further provided with a second flow channel spaced apart from the first flow channel in parallel with a predetermined distance.

5. The battery cell according to claim 4, wherein: The first flow channel and the second flow channel have different cross-sectional areas.

6. The battery cell according to claim 2, wherein: The positive electrode non-overlapping portion is further provided with a fourth flow channel which is parallel to the third flow channel and spaced apart by a predetermined distance.

7. The battery cell according to claim 6, wherein: The third flow channel and the fourth flow channel have different cross-sectional areas.

8. The battery cell according to claim 2, wherein: The negative electrode non-overlapping portion is provided with a first waterproof coating (412c) formed so as not to overlap with the first flow channel, and The positive electrode non-overlapping portion is provided with a second waterproof coating layer formed not to overlap with the third flow channel.

9. The battery cell according to claim 8, wherein: The first waterproof coating is provided along an edge in a direction orthogonal to the negative electrode lead, and The second waterproof coating layer is provided along an edge in a direction orthogonal to the positive electrode lead.

10. The battery cell according to claim 2, wherein: The negative electrode non-overlapping portion is provided with a first barrier tape formed along an edge in a direction orthogonal to the negative electrode lead.

11. The battery cell according to claim 2, wherein: The positive electrode non-overlapping portion is provided with a second barrier tape formed along an edge in a direction orthogonal to the positive electrode lead.

12. A battery module comprising the battery cell according to any one of claims 1 to 11.

13. A method for manufacturing a battery cell, the method comprising the following steps: In a first step, a pouch case having a receiving space configured to receive an electrode assembly is prepared; A second step of attaching a negative electrode insulating film and a positive electrode insulating film to a negative electrode lead and a positive electrode lead electrically connected to the electrode assembly, respectively; and The third step is to accommodate the electrode assembly in the accommodation space of the pouch case and seal the edge of the pouch case. wherein the negative electrode insulating film and / or the positive electrode insulating film is provided with a non-overlapping portion exposed outside the sealing portion of the bag housing, The negative electrode non-overlapping portion of the negative electrode insulating film is provided with a first flow channel configured to allow condensate to move therethrough in a direction orthogonal to the negative electrode lead, and The positive electrode non-overlapping portion of the positive electrode insulating film is provided with a third flow channel configured to allow condensate to move therethrough in a direction orthogonal to the positive electrode lead.

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