Soft package film laminate and soft package type secondary battery

Abstract

The present invention relates to a soft coating film laminate in which a base layer, a gas barrier layer, and a sealant layer are laminated in this order, in which the base layer comprises a polyamide base film. The ratio (H / A) of the height (W / g) (H) of the peak of the polyamide-based film to the melting enthalpy (W * sec / g) (A) with respect to the melting peak of the polyamide-based film obtained by differential scanning calorimetry (DSC) is 0.03 sec-1 or more.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority from Korean Patent Application No. 10-2023-0090095, filed on July 11, 2023, and Korean Patent Application No. 10-2024-0084073, filed on June 26, 2024, the disclosures of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a soft-pack film laminate and a soft-pack secondary battery, and more particularly to a soft-pack film laminate and a soft-pack secondary battery in which defects in the soft-pack appearance that may occur at high sealing temperatures are improved. Background Art

[0004] Generally, secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and lithium-ion polymer batteries. These secondary batteries are used not only in small products such as digital cameras, P-DVDs, MP3 players, mobile phones, PDAs, portable game devices, power tools, and electric bicycles, but also in large products requiring high output such as electric vehicles and hybrid vehicles, energy storage devices, and backup energy storage devices for storing surplus generated electricity or renewable energy.

[0005] To manufacture these secondary batteries, first, an electrode active material slurry is applied to a positive electrode collector and a negative electrode collector to prepare a positive electrode and a negative electrode, respectively. The positive electrode and the negative electrode are then stacked on both sides of a separator to form an electrode assembly having a predetermined shape. The electrode assembly is then placed in a battery case, and the battery case is sealed after an electrolyte is injected.

[0006] Secondary batteries are classified into pouch-type secondary batteries, can-type secondary batteries, and other categories based on the material of the casing that houses the electrode assembly. Pouch-type secondary batteries house the electrode assembly in a pouch made of a flexible polymer material. Can-type secondary batteries house the electrode assembly in a casing made of a material such as metal or plastic.

[0007] The soft pack as the shell of the soft pack type secondary battery is prepared by press-working the flexible soft pack film laminate to form a cup portion. Once the cup portion is formed, the secondary battery can be prepared by accommodating the electrode assembly in the internal accommodation space of the cup portion and sealing the sealing portion.

[0008] Generally, the soft package laminate includes a plurality of layers in which a polymer film such as polyethylene terephthalate is laminated on one surface of a metal gas barrier layer, and a sealant layer is laminated on the other surface thereof.

[0009] Conventionally, increasing the thickness of the gas barrier layer to improve the formability of secondary battery soft packs presents the problem of slow heat transfer to the sealant layer when sealing the soft pack's sealing portion. Consequently, since the soft pack's seal strength decreases as the sealant layer melts more slowly, it is necessary to increase the sealing temperature to apply more heat to the sealing portion to ensure sufficient seal strength. However, if the sealing temperature is raised above 220°C, the base material layer melts, resulting in defects in the soft pack's appearance.

[0010] Therefore, there is a need to develop a soft package film laminate that can improve the appearance defects of the soft package by suppressing the deformation of the base material layer even if sealing is performed by increasing the sealing temperature to 220° C. or more. Summary of the Invention

[0011] Technical issues

[0012] One aspect of the present invention provides a soft-pack film laminate and a soft-pack type secondary battery, which include a polyamide-based film having a narrow melting peak obtained by differential scanning calorimetry in a base material layer, so that even if sealing is performed at a temperature above 220°C, sealing performance and productivity can be ensured and deformation of the appearance of the soft pack can be suppressed.

[0013] Technical Solution

[0014] According to an embodiment, the present invention provides a soft film laminate, in which a base material layer, a gas barrier layer, and a sealant layer are sequentially laminated, wherein the base material layer includes a polyamide-based film, and in a melting peak of the polyamide-based film obtained by a differential scanning calorimeter (DSC), a ratio (H / A) of a peak height (W / g) (H) of the polyamide-based film to a melting enthalpy (W·sec / g) (A) of the polyamide-based film is 0.03 sec -1 More than 0.04 sec -1 above.

[0015] The full width at half maximum of the melting peak of the polyamide-based film may be 5.0° C. or less, preferably 4.5° C. or less, and more preferably 4.0° C. or less.

[0016] The lower limit of the relative moisture content index of the polyamide-based film represented by the following Formula 1 may be 11500 ppm g / cm 2 , preferably 13000 ppm g / cm 2 , more preferably 14000 ppm g / cm 2 , the upper limit of which can be 21500ppm g / cm 2 , preferably 21000 ppm g / cm 2 , more preferably 20000 ppm g / cm 2 .

[0017] [Formula 1]

[0018] Relative moisture index (unit: ppm·g / cm 2 ) = [(water content in soft package) × (soft package density)] × [(thickness of second base material layer) / (total thickness of soft package film laminate)]

[0019] The polyamide-based film may include at least one selected from the group consisting of nylon 6, nylon (6,6), nylon MXD5 (polyxylene adipamide), nylon 4, nylon (4,6), and nylon (4,10), and may preferably include nylon 6.

[0020] The base material layer may have a two-layer structure in which a first base material layer and a second base material layer are sequentially stacked, and the second base material layer may include a polyamide-based film.

[0021] In this case, the thickness of the first base material layer may be 5 μm to 30 μm, preferably 5 μm to 25 μm, and more preferably 7 μm to 20 μm.

[0022] The thickness of the second base material layer may be 5 μm to 30 μm, preferably 7 μm to 29 μm, and more preferably 10 μm to 27 μm.

[0023] The first base material layer may include a polyester base film.

[0024] The gas barrier layer may include at least one selected from the group consisting of aluminum, copper, and stainless steel.

[0025] The thickness of the gas barrier layer may be 20 μm to 100 μm, preferably 30 μm to 90 μm, and more preferably 35 μm to 85 μm.

[0026] The thickness of the sealant layer may be 30 μm to 130 μm, preferably 40 μm to 120 μm, and more preferably 60 μm to 100 μm.

[0027] Furthermore, a pouch-type secondary battery according to another embodiment of the present invention may include a pouch-type battery case prepared by molding any one of the above-described pouch film laminates, and an electrode assembly housed in the pouch-type battery case.

[0028] Beneficial effects

[0029] The soft-pack film laminate according to the present invention includes a polyamide-based film having a narrow melting peak in the base material layer, so that deformation of the base material layer can be suppressed even when the sealing temperature is increased to above 220° C., thereby improving the appearance defects of the soft-pack type secondary battery.

[0030] Furthermore, since the soft-coat laminate according to the present invention suppresses deformation of the base material layer even when the sealing temperature rises to 220°C or higher during sealing, the sealant layer can be melted by applying sufficient heat. Therefore, when sealing the soft-coat laminate, the seal strength can be improved and the sealing time can be reduced, thereby ensuring productivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a cross-sectional view showing the structure of a soft cover laminate according to an embodiment of the present invention.

[0032] Figure 2 is a cross-sectional view showing the structure of a soft cover laminate according to another embodiment of the present invention.

[0033] Figure 3 1 is an exploded view of a pouch-type secondary battery according to the present invention.

[0034] Figure 4 Graph showing the results of differential scanning calorimetry (DSC) evaluation according to Experimental Example 1. DETAILED DESCRIPTION

[0035] The following embodiments, described with reference to the accompanying drawings, will illustrate the advantages and features of the present invention and their implementation methods. However, the present invention may be implemented in different forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. Furthermore, the present invention is limited only by the scope of the claims. Like reference numerals represent like elements throughout.

[0036] It will be understood that the words and terms used in this specification and claims should not be interpreted as having the meanings defined in commonly used dictionaries, and it will be understood that based on the principle that the inventor can appropriately define the meaning of words or terms to best interpret the present invention, the words and terms should be interpreted as having meanings consistent with their meanings in the context of the relevant technology and the technical concept of the present invention.

[0037] The techniques used herein are only for describing specific example embodiments and are not intended to limit the present invention. In this specification, unless otherwise specified, singular terms may include plural forms. It will also be understood that when used in this specification, the terms "include" and / or "comprising" specify the presence of the components described, but do not exclude the presence or addition of one or more other components.

[0038] Hereinafter, the present invention will be described in more detail.

[0039] The present inventors found that the ratio (H / A) of the height (W / g) (H) of the melting peak obtained by differential scanning calorimetry (DSC) to the melting enthalpy (W·sec / g) (A) of the melting peak in the base film layer of the soft film laminate is 0.03 sec -1 In the case of the above polyamide-based film, since deformation of the base film layer can be suppressed even when the soft package film is sealed at a temperature above 220° C., high sealing strength and shortened sealing time can be ensured, thereby completing the present invention.

[0040] Soft film laminate

[0041] The soft film laminate according to the present invention is a soft film laminate having a base material layer, a gas barrier layer, and a sealant layer laminated in this order, wherein the base material layer comprises a polyamide-based film, and in a melting peak of the polyamide-based film obtained by differential scanning calorimetry (DSC), a ratio (H / A) of a peak height (W / g) (H) of the polyamide-based film to a melting enthalpy (W·sec / g) (A) of the polyamide-based film is 0.03 sec -1 Specifically, the soft-coated film laminate according to the present invention may be a soft-coated film laminate.

[0042] In the following, reference will be made to Figure 1 The soft coat laminate according to the present invention and the respective layers included in the soft coat laminate are described in detail.

[0043] Figure 1 is a cross-sectional view of a soft-coat laminate 100 according to the present invention.

[0044] like Figure 1 As shown, the soft film laminate 100 includes a base material layer 110, a gas barrier layer 120, and a sealant layer 130. The base material layer 110, the gas barrier layer 120, and the sealant layer 130 may be sequentially laminated in the soft film laminate 100.

[0045] (1) Base material layer

[0046] According to an embodiment of the present invention, the base material layer 110 is formed as the outermost layer of the soft package laminate 100 to protect the secondary battery from friction and collision with the outside. The base material layer 110 is formed of a polymer so that it can electrically insulate the electrode assembly from the outside.

[0047] The base material layer 110 may include a polyamide-based film. For example, the polyamide-based film may include at least one selected from the group consisting of nylon 6, nylon (6,6), nylon MXD6 (polyxylene adipamide), nylon 4, nylon (4,6), and nylon (4,10), but is not limited thereto. Preferably, the polyamide-based film may include nylon 6, and in this case, due to the excellent elongation properties of nylon 6, there is an advantage in that the moldability of the soft bag can be improved.

[0048] Differential scanning calorimetry (DSC) is a method for analyzing the physical and chemical properties of a sample material by expressing the difference in the amount of heat flowing into the sample material and a reference material as a function of temperature when heated or cooled at a specific temperature. In the melting peak of a graph obtained by differential scanning calorimetry, the area of ​​the peak is defined as the area between the horizontal axis of the graph and the peak, and the unit is W·°C / g. In this case, the melting enthalpy (unit: W·sec / g) of the sample material can be measured by dividing the area of ​​the peak by the heating rate (unit: °C / min) of the DSC instrument. The height (W / g) of the peak is defined as the maximum value of the melting peak and represents the amount of crystals of the sample material melted at the peak temperature. In addition, the full width at half maximum (°C) of the peak is defined as the width of the peak at the position of half the height of the peak and represents the melting temperature distribution of the crystals of the sample material.

[0049] In the melting peak of the polyamide-based film obtained by differential scanning calorimetry (DSC), the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the polyamide-based film may be 0.03 sec -1 More than 0.04 sec -1 above.

[0050] The melting enthalpy of the polyamide-based film indicates the amount of crystals contained in the polyamide-based film, wherein the higher the melting enthalpy, the greater the amount of crystals contained in the polyamide-based film. In addition, the higher the height of the melting peak of the polyamide-based film, the greater the amount of crystals melted at the peak temperature. Therefore, since the present invention adjusts the ratio of the height of the melting peak of the polyamide-based film to the melting enthalpy to 0.03 sec -1 In order to increase the amount of crystals melted at the peak temperature, the present invention uses a polyamide-based film whose melting initial temperature is adjusted to 215°C.

[0051] Specifically, when the above range is met, the melting peak of the polyamide-based film obtained by differential scanning calorimetry can have a relatively narrow and high shape. When the melting enthalpy is the same, the higher the height of the melting peak of the polyamide-based film, the denser the crystals formed. On the contrary, when the melting enthalpy is the same, the lower the height of the melting peak of the polyamide-based film, the sparser the crystals formed, and the amount of crystals melted at a temperature lower than the peak temperature increases relatively.

[0052] Therefore, when the ratio (H / A) of the peak height (H) of the polyamide-based film to the melting enthalpy (A) satisfies the above range, the crystals contained in the polyamide-based film are formed relatively densely, so the melting initial temperature rises. Therefore, when the base material layer contains moisture above a certain level, since the amount of crystal melting when sealing is performed at a temperature of 220°C is relatively small, even if the moisture evaporates, the deformation of the base material layer will occur less. Therefore, since the problem of deformation of the base material layer due to bubbles can be improved, damage to the sealing portion can be prevented, and the durability and life characteristics of the soft-pack type secondary battery can be improved.

[0053] The ratio (H / A) of the height (H) of the peak of polyamide-based film to the melting enthalpy (A) can be regulated by the cooling / heating treatment conditions and the stretching ratio in the preparation process of polyamide-based film. Specifically, when preparing polyamide-based film, as the cooling time is longer, the heat treatment temperature is higher and the heat treatment time is longer, the polyamide-based film can be composed of crystals with uniform size. In addition, in the case where the longitudinal (MD) stretching ratio and the transverse (TD) stretching ratio of the polyamide-based film have similar values, it is easy to have crystals with uniform size. In this case, since the size of the crystals included in the polyamide-based film becomes more uniform, the melting temperature deviation of the crystals decreases, so compared with the total amount of the crystals, the amount of the crystals melted at the peak temperature increases relatively, and therefore the ratio (H / A) can be increased.

[0054] In the melting peak of the polyamide-based film obtained by differential scanning calorimetry (DSC), the ratio (H / A) of the height (W / g) (H) of the peak of the polyamide-based film to the melting enthalpy (W·sec / g) (A) and the ratio of the area of ​​the melting peak in a specific temperature range including the melting initial temperature to the total area of ​​the melting peak may have independent relationships and may have different trends. For example, when the ratio (H / A) of the height (W / g) (H) of the peak of the polyamide-based film to the melting enthalpy (W·sec / g) (A) is 0.03 sec -1 In the above case, the ratio of the area of ​​the melting peak in the range of 210°C to 220°C to the total area of ​​the melting peak can be relatively smaller or larger than the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the polyamide-based film is 0.03sec-1 The ratios in the following cases may be the same as the ratios in this case.

[0055] Even if the ratio of the area of ​​the melting peak in the range of 210°C to 220°C to the total area of ​​the melting peak is relatively large, if the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the polyamide-based film is 0.03 sec -1 Above, deformation of the base material layer when sealing is performed at a temperature of 220°C or above can be prevented. On the contrary, even if the ratio of the area of ​​the melting peak in the range of 210°C to 220°C to the total area of ​​the melting peak is relatively small, if the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the polyamide-based film is 0.03sec -1 Below this, it may be difficult to prevent deformation of the base material layer when sealing is performed at a temperature of 220° C. or higher.

[0056] Furthermore, the full width at half maximum of the melting peak of the polyamide-based film may be 5.0°C or less, preferably 4.5°C or less, and more preferably 4.0°C or less. When the polyamide-based film has the same melting enthalpy, the smaller the full width at half maximum of the melting peak, the denser the crystals contained in the polyamide-based film are formed, and thus the amount of crystals that melt below the peak temperature decreases. Therefore, when the full width at half maximum falls within the above range, even if the base material layer contains a certain level of moisture, the amount of crystals that melt when sealing is performed at a temperature of 220°C is relatively small, so even if the moisture evaporates, the base material layer will be less deformed.

[0057] The lower limit of the relative moisture content index of the polyamide-based film represented by the following formula 1 may be 11500 ppm·g / cm 2 , preferably 13000ppm·g / cm 2 , more preferably 14000 ppm·g / cm 2 , the upper limit of which can be 21500ppm·g / cm 2 , preferably 21000ppm·g / cm 2 , more preferably 20000ppm·g / cm 2 .

[0058] [Formula 1]

[0059] Relative moisture index (unit: ppm·g / cm 2 ) = [(water content in soft package) × (soft package density)] × [(thickness of second base material layer) / (total thickness of soft package film laminate)]

[0060] Regarding the soft film laminate according to the present invention, even when the relative moisture content index of the polyamide-based film is 11500 ppm g / cm 2 In the above case, even when sealing is performed at a temperature of 220° C. or higher, the base material layer does not deform.

[0061] Specifically, when the relative moisture content index is less than 11500 ppm·g / cm 2 In the case of a soft film laminate, there may be a problem of cracking or breaking. In addition, when the relative moisture index is greater than 21500ppm·g / cm 2 In this case, since the toughness of the polyamide-based film is reduced, the formability of the soft pack of the secondary battery may be reduced.

[0062] Therefore, the lower limit of the relative moisture index of polyamide-based membranes is 11500 ppm·g / cm 2 , and its upper limit is 21500ppm·g / cm 2 In this case, since the toughness of the base material layer can be improved, the problem of breakage or cracking when forming the soft package film stack can be prevented to improve the formability of the soft package of the secondary battery.

[0063] The first base material layer 110 may include a polyester base film having wear resistance and heat resistance. For example, the polyester base film may include at least one selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, but is not limited thereto.

[0064] The thickness of the base material layer 110 is 5 μm to 100 μm, preferably 7 μm to 70 μm, and more preferably 15 μm to 60 μm. When the thickness of the base material layer 110 satisfies the above range, the energy density to volume ratio of the secondary battery can be excellent due to excellent external insulation and the small thickness of the entire soft pack.

[0065] The base material layer 110 according to the present invention may have a single layer structure formed of any one material or a composite layer structure formed by laminating two or more materials, respectively.

[0066] Figure 2 is a cross-sectional view showing the structure of a soft cover laminate according to another embodiment of the present invention.

[0067] Reference Figure 2In the case where the base material layer 110 according to the present invention has a composite layer structure, it may have a double-layer structure in which a first base material layer 112 and a second base material layer 114 are stacked in sequence. An adhesive layer may be provided between the layers in the composite layer structure. For example, in the case where the base material layer 110 according to the present invention includes an adhesive layer, it may have a structure in which a first base material layer 112, a first adhesive layer (not shown), and a second base material layer 114 are stacked in sequence. In addition, the base material layer 110 may further include a second adhesive layer (not shown) provided between the second base material layer 114 and the gas barrier layer 120.

[0068] The first base material layer 112, the second base material layer 114, the first adhesive layer, and the second adhesive layer can be formed of materials having different materials and / or physical properties. An interface may exist between each layer of the base material layer 110, including the first base material layer 112, the second base material layer 114, the first adhesive layer, and the second adhesive layer. This means that each layer is different from each other and can be formed separately.

[0069] 1) First base material layer

[0070] The first base material layer 112 may be a layer provided as the outermost layer of the soft package film laminate 100. In this case, the first base material layer 112 may play a role in preventing moisture from penetrating from the outside of the soft package.

[0071] The first base material layer 112 may include at least one selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyamide, cellulose, aramid, nylon, polyester, poly(p-phenylene benzobisoxazole), polyarylate, Teflon, and glass fiber.

[0072] Preferably, the first base material layer 112 may include the above-mentioned polyester base film. Since specific examples of the polyester base film are the same as those described above, detailed descriptions thereof will be omitted.

[0073] In this case, the thickness of the first base material layer can be 5 μm to 30 μm, preferably 5 μm to 25 μm, and more preferably 7 μm to 20 μm. When the thickness of the first base material layer 112 satisfies the above numerical range, it can effectively inhibit moisture from penetrating into the interior of the soft-pack film laminate while ensuring the insulation properties and formability of the soft-pack. In addition, since the total thickness of the soft-pack film laminate is not thick, the energy density to volume ratio of the secondary battery is reduced.

[0074] 2) Second base material layer

[0075] The second base material layer 114 may be a layer provided between the first base material layer 112 and the gas barrier layer 120. In this case, the second base material layer 114 may play a role in improving the formability of the soft package.

[0076] The second base material layer 114 may include the polyamide-based film described above. Since specific examples and features of the polyamide-based film are the same as those described above, detailed descriptions thereof will be omitted.

[0077] The thickness of the second base material layer may be 5 μm to 30 μm, preferably 7 μm to 29 μm, and more preferably 10 μm to 27 μm. When the thickness of the second base material layer satisfies the above range, since the second base material layer is not too thin, the formability of the soft pack can be ensured, and the energy density to volume ratio of the secondary battery caused by excessive increase in the thickness of the soft pack film laminate can be prevented. In addition, the second base material layer can be formed to a uniform thickness.

[0078] 3) First adhesive layer

[0079] The first adhesive layer (not shown) may be a layer disposed between the first base material layer 112 and the second base material layer 114. In this case, the first adhesive layer may serve to adhere the first base material layer 112 and the second base material layer 114 to each other.

[0080] The first adhesive layer may include at least one selected from the group consisting of a polyurethane polymer, an epoxy polymer, and an acrylic polymer, but is not limited thereto. Preferably, the first adhesive layer may include a polyurethane polymer, and in this case, the first adhesive layer may be easily formed and cut while being bonded to the first base material layer 112 and the second base material layer 114.

[0081] The thickness of the first adhesive layer may be 1 μm to 10 μm, preferably 2 μm to 8 μm, and more preferably 2 μm to 5 μm. When the thickness of the first adhesive layer satisfies the above numerical range, sufficient adhesion between the first base material layer 112 and the second base material layer 114 is ensured while preventing a decrease in the energy density to volume ratio of the secondary battery due to an excessive increase in the thickness of the soft envelope laminate.

[0082] 4) Second adhesive layer

[0083] The second adhesive layer (not shown) may be a layer disposed between the second base material layer 114 and the gas barrier layer 120. In this case, the second adhesive layer may serve to bond the second base material layer 114 and the gas barrier layer 120 to each other.

[0084] The second adhesive layer may include at least one selected from the group consisting of a polyurethane-based polymer, an epoxy-based polymer, and an acrylic-based polymer, but is not limited thereto. Preferably, the second adhesive layer may include a polyurethane-based polymer, and in this case, the second adhesive layer may be easily formed and cut while being bonded to the second base material layer 114 and the gas barrier layer 120.

[0085] The thickness of the second adhesive layer may be 1 μm to 10 μm, preferably 2 μm to 8 μm, and more preferably 2 μm to 5 μm. When the thickness of the second adhesive layer satisfies the above numerical range, sufficient adhesion between the second base material layer 114 and the gas barrier layer 120 is ensured while preventing a decrease in the energy density to volume ratio of the secondary battery due to an excessive increase in the thickness of the soft envelope laminate.

[0086] (2) Gas barrier layer

[0087] The gas barrier layer 120 is laminated between the base material layer 110 and the sealant layer 130 to ensure mechanical strength of the pouch, block entry and exit of gas or moisture from outside the secondary battery, and prevent leakage of electrolyte from inside the pouch type battery case.

[0088] The gas barrier layer 120 may be formed of a metal. For example, the gas barrier layer may be a metal thin film including at least one metal selected from the group consisting of aluminum (Al), copper (Cu), stainless steel (SUS), nickel (Ni), titanium (Ti), and invar (INVAR), but is not limited thereto.

[0089] According to an embodiment of the present invention, the gas barrier layer 120 may be formed of an aluminum alloy film. When the gas barrier layer 120 is formed using an aluminum alloy film, the gas barrier layer 120 is lightweight while ensuring mechanical strength greater than a predetermined level, electrochemical performance can be compensated by the electrode assembly and the electrolyte, and heat dissipation performance can be ensured. The aluminum alloy film may contain elements other than aluminum (Al). For example, the aluminum alloy film may contain at least one selected from the group consisting of iron (Fe), copper (Cu), chromium (Cr), manganese (Mn), nickel (Ni), magnesium (Mg), silicon (Si), and zinc (Zn).

[0090] In another example, the gas barrier layer 120 can be formed of a stainless steel film. Specifically, the gas barrier layer 120 can be prepared by molding and / or processing a stainless steel film. Since the gas barrier layer 120 formed of stainless steel has a relatively low thermal conductivity, it effectively prevents or delays the diffusion of heat to other battery cells during thermal runaway, and since it has a relatively high toughness, it can inhibit the generation of cracks in the soft pack during the use of the soft pack type battery. Stainless steel may contain elements other than iron (Fe), for example, at least one selected from the group consisting of copper (Cu), chromium (Cr), manganese (Mn), nickel (Ni), magnesium (Mg), silicon (Si) and zinc (Zn).

[0091] The thickness of the gas barrier layer 120 may be 20 to 100 μm, preferably 30 to 90 μm, and more preferably 35 to 85 μm. When the thickness falls within the above range, the present invention does not cause deformation of the base material layer even when the sealing temperature rises and heat is transferred to the sealant layer. Therefore, when forming a cup portion using a gas barrier layer thicker than conventional gas barrier layers, gas barrier performance and formability can be improved.

[0092] (3) Sealant layer

[0093] When sealing the pouch-type battery case housing the electrode assembly, the sealant layer 130 is used to completely seal the interior of the pouch-type battery case by thermally bonding each other at the sealing portion. To this end, the sealant layer 130 may be formed of a material having excellent thermal bonding strength.

[0094] The sealant layer 130 can be formed of a material having insulating properties, corrosion resistance and sealing properties. Specifically, since the sealant layer 130 is in direct contact with the electrode assembly and / or electrolyte inside the soft-pack battery case, the sealant layer 130 can be formed of a material having insulating properties and corrosion resistance. In addition, since the sealant layer 130 completely seals the interior of the soft-pack battery case to prevent the material from moving between the inside / outside, the sealant layer 130 can be formed of a material having high sealing properties (e.g., excellent thermal bonding strength). In order to ensure such insulating properties, corrosion resistance and sealing, the sealant layer 130 can be formed of a polymer material.

[0095] The sealant layer 130 may be formed of at least one material selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, nylon, polyester, polyphenylene benzobisoxazole, polyarylate, and Teflon, and may preferably be formed of a polyolefin-based resin such as polypropylene (PP) and / or polyethylene (PE). In this case, the polypropylene (PP) may include cast polypropylene (CPP), acid-modified polypropylene (PPa), polypropylene-ethylene copolymer, and / or polypropylene-butylene-ethylene terpolymer.

[0096] The thickness of the sealant layer 130 may be 30 to 130 μm, preferably 40 to 120 μm, and more preferably 60 to 100 μm. When the thickness of the sealant layer satisfies the above range, the formability of the soft package laminate is ensured while ensuring the sealing strength of the sealing portion.

[0097] The sealant layer 130 according to the present invention may have a composite layer structure formed by laminating two or more materials. For example, the sealant layer 130 may have a multilayer structure. An adhesive layer and / or a surface layer may be provided between each layer of the composite layer structure of the sealant layer 130. Since the adhesive layer and / or the surface layer have thermal adhesive properties, the adhesive layer and / or the surface layer may help to bond the various layers of the sealant layer 130. For example, the adhesive layer and / or the surface layer may include a polypropylene-based resin, but is not limited thereto. In addition, the adhesive layer and / or the surface layer may be provided between the sealant layer 130 and the gas barrier layer 120.

[0098] Specifically, the sealant layer 130 according to the present invention may include a first sealant layer 132 and a second sealant layer 134. For example, the sealant layer 130 may be composed of the first sealant layer 132 and the second sealant layer 134. As another example, in addition to the first sealant layer 132 and the second sealant layer 134, the sealant layer 13o may also include a third sealant layer and / or a fourth sealant layer. The individual layers of the sealant layer 13o including the first sealant layer 132 and the second sealant layer 134 may be formed of materials having different materials and / or physical properties. An interface may exist between the various layers included in the sealant layer 130. This means that the various layers are different layers from each other and can be formed separately.

[0099] The soft film laminate of the present invention as described above can be produced by a method for producing a soft film laminate known in the art. For example, the soft film laminate of the present invention can be produced by attaching the base material layer 10 to the upper surface of the gas barrier layer 20 using an adhesive, and forming the sealant layer 30 on the lower surface of the gas barrier layer 20 by coextrusion or adhesive layer. It can also be produced by methods such as dry lamination and sandwich lamination. However, the method for producing the soft film laminate is not limited thereto.

[0100] The total thickness of the soft-coat laminate according to the present invention may be 120 μm to 250 μm, preferably 140 μm to 230 μm, and more preferably 150 μm to 215 μm. When the thickness of the soft-coat laminate meets the above range, the molding depth can be increased while minimizing the reduction in sealing durability and the reduction in battery accommodation space due to the increased thickness of the soft-coat laminate.

[0101] Soft-pack secondary batteries

[0102] Next, a pouch-type secondary battery according to the present invention will be described.

[0103] Figure 3 FIG. 2 is an exploded view of a pouch-type secondary battery 200 according to the present invention.

[0104] like Figure 3 As shown, the soft-pack type secondary battery 200 according to the present invention may include a soft-pack type battery case 210 prepared by molding the above-mentioned soft-pack film laminate and an electrode assembly 260 accommodated in the soft-pack type battery case 210. Specifically, the soft-pack type secondary battery 200 of the present invention may include the soft-pack type battery case 210, the electrode assembly 260, the electrode lead 280, the insulating portion 290 and the electrolyte (not shown).

[0105] In the following, reference will be made to Figure 3 Each configuration of the pouch-type secondary battery of the present invention is described in more detail.

[0106] (1) Soft-pack battery case

[0107] The soft-pack type battery case 210 can be prepared by molding the soft-pack film laminate of the present invention. The inside of the soft-pack type battery case 210 can accommodate the electrode assembly 260. Since the detailed configuration and physical properties of the soft-pack film laminate are the same as above, detailed description is omitted.

[0108] The soft-pack film laminate can be pulled out and stretched by a punch or the like to prepare a soft-pack type battery case 210. Therefore, the soft-pack type battery case 210 may include a cup portion 222 and a receiving portion 224. The receiving portion 224 is a location for receiving the electrode assembly, wherein it may refer to a receiving space formed in the shape of a pocket inside the cup portion 222 as the cup portion 222 is formed.

[0109] According to an embodiment of the present invention, the soft pack type battery case 210 may include a first case 220 and a second case 230. Figure 3 As shown. The first shell 220 includes a receiving portion 224 capable of receiving the electrode assembly 260, and the second shell 230 can cover the receiving portion 224 from the top so that the electrode assembly 260 will not be separated from the outside of the battery shell 210. Figure 3 As shown, the first shell 220 and the second shell 230 can be prepared by connecting one side thereof to each other, but the present invention is not limited thereto, and the first shell 220 and the second shell 230 can be prepared in various ways, for example, the first shell 220 and the second shell 230 are separated from each other and prepared separately.

[0110] According to another embodiment of the present invention, in the case where the cup portion is formed on the soft film laminate, two symmetrical cup portions 222 and 232 can be drawn out adjacent to each other on one soft film laminate. Figure 3 As shown, cup portions 222 and 223 can be formed in the first shell 220 and the second shell 230, respectively. After the electrode assembly 260 is accommodated in the accommodating portion 224 provided in the cup portion 222 of the first shell 220, the bridge portion 240 formed between the two cup portions 222 and 232 can be folded so that the two cup portions 222 and 232 face each other. In this case, the cup portion 232 of the second shell 230 can accommodate the electrode assembly 260 from above. Therefore, since the two cup portions 222 and 232 accommodate one electrode assembly 260, an electrode assembly 260 with a greater thickness than that of a single cup portion 222 can be accommodated. In addition, since one edge of the secondary battery 200 is formed by folding the soft-pack battery case 210, the number of edges to be sealed can be reduced when the sealing process is performed later. Therefore, the process speed of the soft-pack secondary battery 200 can be increased, and the number of sealing processes can be reduced.

[0111] The soft pack type battery case 210 can be sealed in a state where it accommodates the electrode assembly 260, thereby exposing a portion of the electrode lead 280, that is, the terminal portion, which will be described later. Specifically, when the electrode lead 280 is connected to the electrode tab 270 of the electrode assembly 260 and the insulating portion 290 is formed at a portion of the electrode lead 280, the electrode assembly 260 is accommodated in the accommodating portion 224 provided in the cup portion 222 of the first case 220, and the second case 230 can cover the accommodating portion 224 from the top. Subsequently, the electrolyte is injected into the accommodating portion 224, and the sealing portion 250 formed at the edge of the first case 220 and the edge of the second case 230 can be sealed.

[0112] The sealing portion 250 may be used to seal the accommodating portion 224. Specifically, the sealing portion 250 may seal the accommodating portion 224 while being formed along the edge of the accommodating portion 224. The temperature at which the sealing portion 250 is sealed may be in the range of 180°C to 250°C, particularly 200°C to 250°C, and more particularly 210°C to 240°C. When the sealing temperature satisfies the above numerical range, the soft pack type battery case 210 may ensure sufficient sealing strength through thermal bonding.

[0113] (2) Electrode assembly

[0114] The electrode assembly 260 may be inserted into the pouch type battery case 210 and may be sealed by the pouch type battery case 210 after injecting an electrolyte.

[0115] The electrode assembly 260 may be formed by sequentially stacking a positive electrode, a separator, and a negative electrode. Specifically, the electrode assembly 260 may include two types of electrodes, such as a positive electrode and a negative electrode, and a separator disposed between the electrodes to insulate the electrodes from each other.

[0116] The positive and negative electrodes can each be constructed by applying an active material slurry to an electrode current collector in the form of a metal foil or mesh containing aluminum or copper. Typically, the slurry is formed by stirring particulate active material, an auxiliary conductor, a binder, and a conductive agent in the presence of a solvent. The solvent can be removed in a subsequent step.

[0117] A slurry in which an electrode active material, a binder, and / or a conductive agent are mixed is applied to a positive electrode collector and a negative electrode collector to prepare a positive electrode and a negative electrode, and the positive electrode and the negative electrode can be stacked on both sides of a separator to prepare an electrode assembly 260 in a predetermined shape. Types of the electrode assembly 260 may include a stacked type, a jelly roll type, and a stacked folded type, but are not limited thereto.

[0118] The electrode assembly 260 may include an electrode tab 270 .

[0119] The electrode terminal tab 270 is connected to each of the positive electrode and the negative electrode of the electrode assembly 260 and protrudes from the electrode assembly 260 to the outside, so that it can be a path through which electrons can move between the inside and the outside of the electrode assembly 260. The electrode collector included in the electrode assembly 260 can be composed of a portion coated with an electrode active material and an end portion (i.e., a non-coating portion) that is not coated with the electrode active material. The electrode terminal tab 270 can be formed by cutting the non-coating portion, or the electrode terminal tab 270 can be formed by connecting a separate conductive member to the non-coating portion by ultrasonic welding or the like. As shown in FIG. Figure 3 As shown, the electrode tabs 270 may protrude in different directions of the electrode assembly 260, respectively, but are not limited thereto, and may be formed to protrude in various directions, for example, the electrode tabs 270 protrude side by side from one side of the electrode assembly 260 in the same direction.

[0120] (3) Electrode leads

[0121] The electrode lead 280 may supply power to the outside of the secondary battery 200. The electrode lead 280 may be connected to the electrode tab 270 of the electrode assembly 260 by spot welding or the like.

[0122] The electrode lead 280 is connected to the electrode assembly 260 and may protrude to the outside of the soft-pack type battery case 210 via the sealing portion 250. Specifically, one end of the electrode lead 280 is connected to the electrode assembly 260, particularly the electrode tab 270, and the other end of the electrode lead 280 may protrude to the outside of the soft-pack type battery case 210.

[0123] Electrode lead 280 may include a positive electrode lead 282, one end of which is connected to positive electrode tab 272 and extends in the direction in which positive electrode tab 272 protrudes; and a negative electrode lead 284, one end of which is connected to negative electrode tab 271 and extends in the direction in which negative electrode tab 271 protrudes. The other ends of both positive electrode lead 282 and negative electrode lead 284 may protrude outside of battery case 210. Thus, electricity generated within electrode assembly 260 can be supplied to the outside. Furthermore, since positive electrode tab 272 and negative electrode tab 271 are formed to protrude in various directions, positive electrode lead 282 and negative electrode lead 284 may also extend in various directions. The materials of positive electrode lead 282 and negative electrode lead 284 may be different from each other. That is, the positive electrode lead 282 can be formed of the same aluminum (Al) material as the positive electrode current collector, and the negative electrode lead 284 can be formed of the same copper (Cu) material or nickel (Ni)-coated copper material as the negative electrode current collector. Since the portion of the electrode lead 280 protruding to the outside of the battery case 210 becomes a terminal portion, it can be electrically connected to an external terminal.

[0124] (4) Insulation

[0125] The insulating portion 290 prevents the electricity generated from the electrode assembly 260 from flowing to the battery case 210 through the electrode lead 280 and can maintain the sealing of the battery case 210. To this end, the insulating portion 290 can be formed of an insulator having non-conductivity that does not conduct electricity well. Generally, as the insulating portion 290, an insulating tape or film that is easily attached to the electrode lead 280 and is relatively thin is widely used, but the present invention is not limited thereto, and any member that can insulate the electrode lead 280 can be used.

[0126] The insulating portion 290 may be provided to surround the outer peripheral surface of the electrode lead 280. Specifically, at least a portion of the electrode lead 280 may be surrounded by the insulating portion 290. In this case, the insulating portion 290 may be provided between the electrode lead 280 and the soft-pack type battery case 210. The insulating portion 290 may be limitedly located at the sealing portion 250, and the first shell 220 and the second shell 230 of the soft-pack type battery case 210 are heat-welded to the sealing portion 250, and the electrode lead 280 may be adhered to the battery case 210.

[0127] (5) Electrolytes

[0128] The soft-pack secondary battery 200 according to the present invention may further include an electrolyte (not shown) injected into the soft-pack battery case 210. The electrolyte is used to move lithium ions generated by the electrochemical reaction of the electrodes during the charge and discharge of the secondary battery 200, wherein the electrolyte may include a non-aqueous organic electrolyte solution that is a mixture of a lithium salt and an organic solvent or a polymer using a polymer electrolyte. In addition, the electrolyte may include a sulfide-based, oxide-based, or polymer-based solid electrolyte, and the solid electrolyte may have flexibility that is easily deformed by an external force.

[0129] Hereinafter, the present invention will be described in detail based on specific examples. However, the following examples are only used to illustrate the present invention, and the scope of the present invention is not limited thereto. It is obvious to those skilled in the art that various modifications and variations can be made within the scope and technical spirit of the present invention. Such modifications and variations fall within the scope of the claims included herein.

[0130] Example 1

[0131] A base material layer was formed by sequentially laminating a 25 μm thick nylon 6 film A, a 12 μm thick second adhesive film, and a 12 μm thick polyethylene terephthalate (PET) film, each having the thermal properties shown in Table 1 below, on one surface of a 60 μm thick aluminum (AL) alloy film using a dry lamination method using a polyurethane adhesive. In this case, the polyurethane adhesive was applied so that the adhesive layer had a thickness of 3 μm. Next, a soft film laminate was prepared by co-extruding a 40 μm thick acid-modified polypropylene (PPa) film and a 40 μm thick polypropylene (PP) film onto the other surface of the aluminum alloy film to form an 80 μm thick sealant layer.

[0132] Example 2

[0133] A base material layer was formed by sequentially laminating a 25 μm thick nylon 6 film B, a 12 μm thick second adhesive film, and a 12 μm thick polyethylene terephthalate (PET) film, each having the thermal properties shown in Table 1 below, on one surface of a 60 μm thick aluminum (AL) alloy film using a dry lamination method using a polyurethane adhesive. In this case, the polyurethane adhesive was applied so that the adhesive layer had a thickness of 3 μm. Next, a soft-coat film laminate was prepared by coextruding a 30 μm thick acid-modified polypropylene (PPa) film, a 30 μm thick cast polypropylene (CPP) film, and a 20 μm thick polypropylene (PP) film on the other surface of the aluminum alloy film to form an 80 μm thick sealant layer.

[0134] Comparative Example 1

[0135] A base material layer was formed by sequentially laminating a 25 μm thick nylon 6 film C, a 12 μm thick second adhesive film, and a 12 μm thick polyethylene terephthalate (PET) film, each having the thermal properties shown in Table 1 below, onto one surface of a 60 μm thick aluminum (AL) alloy film using a dry lamination method using a polyurethane adhesive. In this case, the polyurethane adhesive was applied so that the adhesive layer had a thickness of 3 μm. Next, a soft-coat film laminate was prepared by coextruding a 30 μm thick acid-modified polypropylene (PPa) film and a 50 μm thick cast polypropylene (CPP) film onto the other surface of the aluminum alloy film to form an 80 μm thick sealant layer.

[0136] Comparative Example 2

[0137] A base material layer was formed by sequentially laminating a 25 μm thick nylon 6 film D, a 12 μm thick second adhesive film, and a 12 μm thick polyethylene terephthalate (PET) film, each having the thermal properties shown in Table 1 below, on one surface of a 60 μm thick aluminum (AL) alloy film using a dry lamination method using a polyurethane adhesive. In this case, the polyurethane adhesive was applied so that the adhesive layer had a thickness of 3 μm. Next, a soft-coat film laminate was prepared by coextruding a 30 μm thick polypropylene (PP) film and a 50 μm thick polypropylene film on the other surface of the aluminum alloy film to form an 80 μm thick sealant layer.

[0138] Comparative Example 3

[0139] A base material layer was formed by sequentially laminating a 15 μm thick nylon 6 film E, a 12 μm thick second adhesive film, and a 12 μm thick polyethylene terephthalate (PET) film, each having the thermal properties shown in Table 1 below, onto one surface of a 40 μm thick aluminum (AL) alloy film using a dry lamination method using a polyurethane adhesive. In this case, the polyurethane adhesive was applied so that the adhesive layer had a thickness of 3 μm. Next, a soft-coat film laminate was prepared by coextruding an 80 μm thick cast polypropylene (CPP) film onto the other surface of the aluminum alloy film to form an 80 μm thick sealant layer.

[0140] Comparative Example 4

[0141] A base material layer was formed by sequentially laminating a 15 μm thick nylon 6 film F, a 12 μm thick second adhesive film, and a 12 μm thick polyethylene terephthalate (PET) film, each having the thermal properties shown in Table 1 below, onto one surface of a 40 μm thick aluminum (AL) alloy film using a dry lamination method using a polyurethane adhesive. In this case, the polyurethane adhesive was applied so that the adhesive layer had a thickness of 3 μm. Next, a soft-coat film laminate was prepared by coextruding an 80 μm thick cast polypropylene (CPP) film onto the other surface of the aluminum alloy film to form an 80 μm thick sealant layer.

[0142] Experimental Example 1 - Measurement of Thermal Properties of Nylon Membranes

[0143] The soft coating film laminates of Examples 1 and 2 and Comparative Examples 1 to 4 prepared as described above were each loaded into a differential scanning calorimeter (DSC, TA Instruments, DSC250) and heated to 280°C at a heating rate of 10°C / min to confirm the thermal properties of the soft coating film laminates. In this case, the thermal properties of the nylon 6 films included in each of Examples 1 and 2 and Comparative Examples 1 to 4 were measured by the melting peak of the nylon 6 film appearing in the temperature range of 200°C to 230°C of the DSC instrument. The results are shown in Tables 1 and 2 below. Figure 4 Shown in.

[0144] [Table 1]

[0145]

[0146] Referring to Table 1, it can be confirmed that the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the nylon membranes A and B included in Examples 1 and 2 is 0.03 sec -1 and the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the nylon films C, D, E, and F included in Comparative Examples 1 to 4 is less than 0.03 sec -1 Referring to Table 1, it can be confirmed that the ratio (Y / X) of the area (Y) of the melting peak in the range of 210°C to 220°C to the total area (X) of the melting peak of the nylon membrane A included in Example 1 is smaller than those of the nylon membranes C, D, and E included in Comparative Examples 1 to 3, respectively, but the ratio (Y / X) of the area (Y) of the melting peak in the range of 210°C to 220°C to the total area (X) of the melting peak is greater than that of the nylon membrane F included in Comparative Example 4. That is, it can be understood that the ratio (H / A) of the height (W / g) (H) of the peak to the melting enthalpy (W·sec / g) and the ratio (Y / X) of the area (Y) of the melting peak in the range of 210°C to 220°C to the total area (X) of the melting peak according to the present invention have an independent relationship.

[0147] Experimental Example 2-Is the appearance of the sealing part deformed?

[0148] The water content per unit weight of the soft coating laminate was changed by adjusting the moisture content in the chamber in which each soft coating laminate prepared in Examples 1 and 2 and Comparative Examples 1 to 4 was stored. Then, for Examples 1 and 2 and Comparative Examples 1 to 4, the relative moisture index of the second base material layer prepared according to the following formula 1 was 6000 ppm·g / cm 2 , 9000ppm·g / cm 2 、11500ppm·g / cm 2 and 14000ppm·g / cm 2 Five soft envelope film stacks each.

[0149] [Formula 1]

[0150] Relative moisture content index = [(soft pack moisture content) × (soft pack density)] × [(second base material layer thickness) / (total thickness of soft pack film laminate)]

[0151] After that, after each soft-pack film stack was cut into a size of 266 mm in width and 200 mm in length, and then folded in half into a size of 133 mm in width and 200 mm in length so that the sealant layers were in contact with each other, each soft-pack type battery case was prepared by sealing the end of the long side (200 mm) under the following conditions.

[0152] - Sealing conditions: sealing at a sealing strip area of ​​200 mm x 8 mm and 220°C for 1.6 seconds.

[0153] Next, each of the sealed pouch-type battery cases was visually inspected to see if the seal portion was deformed due to bubbles generated in the second base material layer in the seal portion. The results are shown in Table 2 below.

[0154] O: The seal is deformed due to the generation of bubbles

[0155] ×: No bubbles are generated and the seal portion is not deformed

[0156] [Table 2]

[0157]

[0158] According to Table 2, the ratio of the height of the melting peak to the melting enthalpy of the polyamide-based film is 0.03 sec -1 The above Examples 1 and 2 are different from Comparative Examples 1 to 4 because when sealing is performed at 220°C, even when the relative moisture content is 11500 ppm·g / cm 2 In the above case, no bubbles were generated in the second base material layer, and therefore it was confirmed that the appearance of the seal portion was not deformed.

[0159] (Explanation of Reference Numerals)

[0160] 100: Soft film laminate

[0161] 110: Base material layer

[0162] 112: First base material layer

[0163] 114: Second base material layer

[0164] 120: Gas barrier layer

[0165] 130: Sealant layer

[0166] 200: Soft pack secondary battery

[0167] 210: Soft-pack housing

[0168] 220: First shell

[0169] 222: Cup Department

[0170] 224: Accommodation

[0171] 230: Second shell

[0172] 232: Cup Department

[0173] 240: Bridge

[0174] 250: Sealing part

[0175] 260: Electrode assembly

[0176] 270: Electrode terminal

[0177] 272: Positive terminal lug

[0178] 274: Negative terminal lug

[0179] 280: Electrode lead

[0180] 282: Positive lead

[0181] 284: Negative lead

[0182] 290: Insulation

Claims

1. A soft film laminate, wherein a base material layer, a gas barrier layer and a sealant layer are laminated in this order, in, The base material layer includes a polyamide-based film, and In the melting peak of the polyamide-based film obtained by differential scanning calorimetry (DSC), the ratio (H / A) of the peak height (W / g) (H) to the melting enthalpy (W·sec / g) (A) of the polyamide-based film is 0.03 sec- 1 above.

2. The soft-coated laminate according to claim 1, wherein The full width at half maximum of the melting peak of the polyamide-based film is 5.0° C. or less.

3. The soft-coated laminate according to claim 1, wherein The lower limit of the relative moisture content index of the polyamide-based film represented by Formula 1 is 11500 ppm·g / cm 2 , [Formula 1] Relative moisture index (ppm·g / cm 2 )=[(water content in the soft package)×(soft package density)]×[(thickness of the second base material layer) / (total thickness of the soft package film laminate)].

4. The soft-coated laminate according to claim 1, wherein The polyamide-based film includes at least one selected from the group consisting of nylon 6, nylon (6,6), nylon MXD5 (poly(m-xylylene adipamide), nylon 4, nylon (4,6), and nylon (4,10).

5. The soft-coated laminate according to claim 1, wherein The base material layer has a two-layer structure in which a first base material layer and a second base material layer are sequentially stacked, and the second base material layer includes the polyamide-based film. The soft-coated laminate according to claim 5 , wherein: The thickness of the second base material layer is 5 μm to 30 μm.

7. The soft-coated laminate according to claim 5, wherein The thickness of the first base material layer is 5 μm to 30 μm.

8. The soft-coated laminate according to claim 5, wherein The first base material layer includes a polyester base film.

9. The soft-coated laminate according to claim 1, wherein The gas barrier layer includes at least one selected from the group consisting of aluminum, copper, and stainless steel.

10. The soft-coated laminate according to claim 1, wherein The gas barrier layer has a thickness of 20 μm to 100 μm.

11. The soft-coated laminate according to claim 1, wherein The sealant layer has a thickness of 30 μm to 130 μm.

12. A soft-pack secondary battery comprising: A soft-pack type battery case prepared by molding the soft-pack film laminate according to any one of claims 1 to 11; as well as An electrode assembly is housed in the pouch-type battery case.

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