Protection film sheet and electrode laminate manufacturing apparatus including same

Abstract

The protection film sheet according to one embodiment of the present invention includes: a first layer including at least one selected from the group consisting of polyimide (PI), polyethylene terephthalate (PET), polypropylene (PP), polycyclohexylenedimethylene terephthalate (PCT), and polyethylene naphthalate (PEN); and a second layer including silicon (Si) laminated on the first layer, wherein the protection film sheet has a moisture content of 0.001 ppm or more to 5000 ppm or less, or the protection film sheet further includes, on an outer surface thereof, a coating layer formed of a ceramic material.　The electrode laminate manufacturing apparatus according to another embodiment of the present invention includes the protection film sheet described above and is configured to manufacture an electrode laminate in which a first separator, a negative electrode, a second separator, and a positive electrode are sequentially laminated, the apparatus comprising: a laminating unit for bonding an electrode laminate sheet in which the multiple negative electrodes are disposed to be spaced apart from each other on a first separator sheet and the multiple positive electrodes are disposed to be spaced apart from each other on a second separator sheet; and a first sealing unit for bonding the first separator sheet and the second separator sheet to each other, wherein the protection film sheet is positioned between the laminating unit and the electrode laminate sheet and between the first sealing unit and the electrode laminate sheet, and extends along a moving direction of the electrode laminate sheet.

Description

Protective film sheet and electrode laminate manufacturing device including the same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0085212, filed June 28, 2024, the entire contents of which are incorporated herein by reference.

[0003] The present invention relates to a protective film sheet and an electrode laminate manufacturing device including the same, and more particularly, to a protective film sheet having high heat resistance that does not undergo thermal deformation in a production line in which a process in which heat of a predetermined temperature or higher is applied is performed, and an electrode laminate manufacturing device including the same.

[0004] As technological development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing. Among these secondary batteries, lithium secondary batteries, which have high energy density and voltage, long cycle life, and low self-discharge rate, are being commercialized and widely used.

[0005] These secondary batteries are classified into cylindrical and prismatic batteries, in which the electrode stack is built into a cylindrical or prismatic metal can, and pouch-type batteries, in which the electrode stack is built into a pouch-type case made of aluminum laminate sheets, depending on the shape of the battery case. Here, the electrode stack built into the battery case is a power plant capable of charging and discharging, consisting of a positive electrode, a negative electrode, and a separator structure interposed between the positive electrode and the negative electrode, and is classified into a jelly-roll type in which a separator is interposed between long sheet-shaped positive and negative electrodes coated with an active material and wound, and a stack type in which a plurality of positive electrodes and negative electrodes are sequentially stacked while interposing the separator between them.

[0006] Among these, pouch-type batteries, which have a structure in which a stacked or stacked / folded electrode laminate is built into a pouch-type battery case made of aluminum laminate sheet, are gradually increasing in usage due to reasons such as low manufacturing cost, small weight, and easy deformation.

[0007] Among stacked electrode laminates, in order to manufacture a lamination & stack type (L&S) electrode laminate in which unit cells are first manufactured using anodes, separators, and cathodes and then these unit cells are stacked, the unit cells must first be manufactured.

[0008] Typically, to manufacture a unit cell, a separator is laminated on the upper and lower surfaces of the central electrode while the central electrode moves in one direction by a conveyor belt or the like. Thereafter, an upper electrode is further laminated at the top. In some cases, a lower electrode may be further laminated at the bottom. A laminating process is then performed, applying heat and pressure to the laminated body of the electrode and separator. As this laminating process is performed, the electrode and separator are bonded together, allowing the unit cell to be firmly formed.

[0009] Additionally, to prevent folding of the separator, the lamination process must include a step of bonding a pair of laminated separators with a central electrode between them. In particular, to prevent deformation or damage to the electrodes and / or separators that may occur during the sealing of the separator using a conventional lamination process, the sealing process in the conventional laminating process was performed with a protective film sheet inserted between the sealing device and the unit cell.

[0010] However, there were problems such as the protective film sheet being deformed by heat during the laminating process or some of the separator being transferred to the protective film, so it was necessary to discard the protective film sheet after one use.

[0011] Accordingly, there is a need to develop a reusable protective film sheet and an electrode laminate manufacturing device including the same while preventing thermal deformation and separator transfer during the laminating process.

[0012] The problem to be solved by the present invention is to provide a protective film sheet having high heat resistance that does not undergo thermal deformation in a production line in which a process in which heat above a predetermined temperature is applied is performed, and an electrode laminate manufacturing device including the same.

[0013] The problems to be solved by the present invention are not limited to the problems described above, and problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention pertains from this specification and the attached drawings.

[0014] A protective film sheet according to one embodiment of the present invention comprises a first layer including at least one material selected from the group consisting of PI (Polyimide), PET (polyethylene terephthalate), PP (Polypropylene), PCT (Polycyclohexylenedimethylene terephthalate), and PEN (Polyethylene naphthalate), and a second layer made of Si (Silicon) laminated on the first layer, wherein the protective film sheet has a moisture content of 0.001 ppm or more and 5000 ppm or less, or further comprises a coating layer made of a ceramic material on the outer surface of the protective film sheet.

[0015] The above protective film sheet may not be deformed even at a temperature of 40 degrees Celsius or higher and 150 degrees Celsius or lower and a pressure of 0.1 Mpa or higher and 150 Mpa or lower.

[0016] The protective film sheet has a moisture content of 0.001 ppm or more and 5000 ppm or less, and includes a coating layer made of a ceramic material on the outer surface of the protective film sheet.

[0017] According to another embodiment of the present invention, an electrode laminate manufacturing device comprises the above-described protective film sheet, and manufactures an electrode laminate in which a first separator, a negative electrode, a second separator, and a positive electrode are sequentially laminated, the device comprising: a laminating unit for bonding electrode laminate sheets in which a plurality of the negative electrodes are arranged to be spaced apart from each other on a first separator sheet and a plurality of the positive electrodes are arranged to be spaced apart from each other on a second separator sheet; and a first sealing unit for bonding the first separator sheet and the second separator sheet to each other, wherein the protective film sheet extends along a moving direction of the electrode laminate sheet and is positioned between the laminating unit and the electrode laminate sheet and between the first sealing unit and the electrode laminate sheet.

[0018] It includes a first protective film reel and a second protective film reel spaced apart from each other with the laminating portion and the sealing portion therebetween, the protective film sheet is unwound from the first protective film reel and then wound up from the second protective film reel, and the protective film sheet wound up from the second protective film reel can be reused.

[0019] The protective film sheet wound on the second protective film reel can be re-wound on the first protective film reel.

[0020] The second protective film reel on which the protective film sheet is wound can be interchanged with the first protective film reel on which the protective film sheet is already wound.

[0021] The second layer of the protective film sheet may face the electrode laminated sheet, and the first layer of the protective film sheet may face the first sealing portion.

[0022] The apparatus further includes a reel from which the first separator sheet, the negative electrode sheet, the second separator sheet, and the positive electrode sheet are each unwound, and further includes a first cutting unit positioned before the laminating unit based on the moving direction of the electrode laminated sheet and cutting the negative electrode sheet and the positive electrode sheet, respectively, and the first cutting unit cuts the negative electrode from the negative electrode sheet and cuts the positive electrode from the positive electrode sheet, and the first protective film reel may be positioned after the first cutting unit.

[0023] In the above electrode laminated sheet, a pair of the cathodes and the anode may be arranged on the same vertical line, and another pair of the cathodes and the anode positioned adjacent to the pair of the cathodes and the anode may be spaced apart from each other.

[0024] The first sealing portion joins the first sealing area of ​​the electrode laminate sheet, and the first sealing area is the first separator sheet portion and the second separator sheet portion positioned between the pair of the negative electrode and the positive electrode and the other pair of the negative electrode and the positive electrode, and the protective film sheet may be positioned between the first sealing portion and the electrode laminate sheet.

[0025] The first sealing portion includes a first upper sealing portion positioned on the upper portion of the electrode laminated sheet and a first lower sealing portion positioned on the lower portion of the electrode laminated sheet, and the first upper sealing portion includes a first upper main body portion and a plurality of first upper protrusions spaced apart from each other along an outer circumferential surface of the first upper main body portion, and the plurality of first upper protrusions may extend along a longitudinal direction of the first upper main body portion.

[0026] The above protective film sheet is positioned between the first upper protrusion and the first sealing area, and the first upper protrusion can press the first sealing area.

[0027] The electrode laminate sheet may further include a second cutting section positioned after the first sealing section in the direction of movement thereof, and cutting the first sealing area to manufacture a plurality of electrode laminates, and the second protective film reel may be positioned before the second cutting section.

[0028] The second sealing portion further includes a second sealing portion that joins the second sealing area of ​​the electrode laminate sheet, wherein the second sealing area extends along the longitudinal direction of the first separator sheet and the second separator sheet, and is a portion of the first separator sheet where the negative electrode is not arranged and a portion of the second separator sheet where the positive electrode is not arranged, and the second protective film reel can be positioned before the second sealing portion.

[0029] The protective film sheet according to an embodiment of the present invention and the electrode laminate manufacturing device including the same may have the advantage of cost reduction and productivity improvement because it does not undergo thermal deformation in a production line in which a process in which heat of a predetermined temperature or higher is applied is performed.

[0030] The effects of the present invention are not limited to the effects described above, and effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention pertains from this specification and the attached drawings.

[0031] FIG. 1 is a drawing showing an electrode laminate manufacturing device according to one embodiment of the present invention.

[0032] Fig. 2 is a top view showing a portion of the electrode laminate sheet of Fig. 1.

[0033] Fig. 3 is a cross-sectional view showing a protective film sheet included in the electrode laminate manufacturing device of Fig. 1.

[0034] Fig. 4(a) shows a conventional protective film sheet, and Fig. 4(b) is a drawing showing the surface of the protective film sheet of Fig. 3.

[0035] Figures 5 and 6 are drawings showing the results of comparative examples and examples according to Experimental Example 1.

[0036] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. The present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0037] In order to clearly explain the present invention, parts that are not related to the description are omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0038] Additionally, throughout the specification, whenever a part is said to “include” a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0039] Fig. 1 is a drawing showing an electrode laminate manufacturing device according to one embodiment of the present invention. Fig. 2 is a top view showing a portion of the electrode laminate sheet of Fig. 1.

[0040] Referring to FIG. 1, an electrode laminate manufacturing device (1000) according to one embodiment of the present invention is an electrode laminate manufacturing device (1000) that manufactures an electrode laminate (100) in which a first separator (141), a negative electrode (121), a second separator (131), and an anode (111) are sequentially laminated.

[0041] An electrode laminate manufacturing device (1000) according to the present embodiment includes a laminating unit (1701, 1702, 1801, 1802) for bonding an electrode laminate sheet (200) in which a plurality of negative electrodes (121) are arranged spaced apart from each other on a first separator sheet (140) and a plurality of positive electrodes (111) are arranged spaced apart from each other on a second separator sheet (130); and a first sealing unit (1901, 1902) for bonding the first separator sheet (140) and the second separator sheet (130) to each other.

[0042] More specifically, the electrode laminate manufacturing device (1000) may further include a reel from which the first separator sheet (140), the negative electrode sheet (120), the second separator sheet (130), and the positive electrode sheet (110) are each unwound.

[0043] For example, the first separator sheet (140) is wound on a first separator reel (1400), and the first separator sheet (140) can be unwound from the first separator reel (1400). The second separator sheet (130) is wound on a second separator reel (1300), and the second separator sheet (130) can be unwound from the second separator reel (1300). The negative electrode sheet (120) is wound on a negative electrode reel (1200), and the negative electrode sheet (120) can be unwound from the negative electrode reel (1200). The positive electrode sheet (110) is wound on a positive electrode reel (1100), and the positive electrode sheet (110) can be unwound from the positive electrode reel (1100).

[0044] The negative electrode sheet (120) can be manufactured by applying a slurry of a negative electrode active material, a conductive material, and a binder onto a negative electrode current collector, and then drying and pressing the same, and the positive electrode sheet (110) can be manufactured by applying a slurry of a positive electrode active material, a conductive material, and a binder onto a positive electrode current collector, and then drying and pressing the same. However, the manufacturing method of the negative electrode sheet (120) and the positive electrode sheet (110) is not limited thereto, and any method for manufacturing the negative electrode sheet (120) and the positive electrode sheet (110) in general in the relevant technical field can be included in the present embodiment.

[0045] Referring to FIG. 1, the electrode laminate manufacturing device (1000) according to the present embodiment may further include a first cutting unit (1601) positioned before the laminating unit (1701, 1702, 1801, 1802) based on the movement direction of the electrode laminate sheet (200), and for cutting the negative electrode sheet (120) and the positive electrode sheet (110), respectively.

[0046] More specifically, the first cutting portion (1601) can cut the negative electrode (121) from the negative electrode sheet (120) and cut the positive electrode (111) from the positive electrode sheet (110). For example, the first cutting portion (1601) can cut a plurality of negative electrodes (121) spaced apart from the negative electrode sheet (120) at equal intervals, and can cut a plurality of positive electrodes (111) spaced apart from the positive electrode sheet (110) at equal intervals. However, for convenience of explanation, the first cutting portion (1601) is illustrated only at a position corresponding to the positive electrode sheet (110) in FIG. 1, but the first cutting portion (1601) can also be positioned at a position corresponding to the negative electrode sheet (120). As described below, the first protective film reel (1501a, 1502a) from which the protective film sheet (500) is ejected can be positioned after the first cutting section (1601).

[0047] Accordingly, the electrode laminate manufacturing device (1000) according to the present embodiment has the advantage that, since the first cutting unit (1601) is not a high temperature and / or high pressure process, the protective film sheet (500) can be placed only at a position corresponding to a configuration in which a high temperature and / or high pressure process is performed, thereby reducing costs and improving productivity.

[0048] The protective film sheet (500) extends along the moving direction of the electrode lamination sheet (200) and can be positioned between the laminating portion (1701, 1702, 1801, 1802) and the electrode lamination sheet (200) and between the first sealing portion (1901, 1902) and the electrode lamination sheet (200).

[0049] More specifically, the protective film sheet (500) can be wound or unwound on a first protective film reel (1501a, 1502a) and a second protective film reel (1501b, 1502b). As shown in FIG. 1, the first protective film reel (1501a, 1502a) and the second protective film reel (1501b, 1502b) can be spaced apart from each other with the laminating portion (1701, 1702, 1801, 1802) and the first sealing portion (1901, 1902) interposed therebetween. In addition, as shown in FIG. 1, the first protective film reel (1501a, 1502a) and the second protective film reel (1501b, 1502b) can be disposed both above and below the electrode laminate sheet (200). For example, a first upper protective film reel (1501a) and a second upper protective film reel (1501b) may be arranged on the upper side of the electrode laminate sheet (200), and a first lower protective film reel (1502a) and a second lower protective film reel (1502b) may be arranged on the lower side of the electrode laminate sheet (200).

[0050] For example, the protective film sheet (500) may be unwound from the first protective film reel (1501a, 1502a) and then unwound from the second protective film reel (1501b, 1502b). In other words, the protective film sheet (500) unwound from the first protective film reel (1501a, 1502a) may extend between the laminating portions (1701, 1702, 1801, 1802) and the electrode laminated sheet (200) and between the first sealing portions (1901, 1902) and the electrode laminated sheet (200). Additionally, the protective film sheet (500) can be wound on a second protective film reel (1501b, 1502b) positioned after the first sealing portion (1901, 1902) based on the moving direction of the electrode lamination sheet (200).

[0051] More specifically, the protective film sheet (500) wound on the second protective film reel (1501b, 1502b) can be reused. For example, the protective film sheet (500) wound on the second protective film reel (1501b, 1502b) can be rewound on the first protective film reel (1501a, 1502a). In another example, the second protective film reel (1501b, 1502b) on which the protective film sheet (500) is wound can be interchanged with the first protective film reel (1501a, 1502a) from which the protective film sheet (500) is already unwound.

[0052] Accordingly, in the electrode laminate manufacturing device (1000) according to the present embodiment, the protective film sheet (500) can be repeatedly moved along between the laminating portion (1701, 1702, 1801, 1802) and the first sealing portion (1901, 1902) and the electrode laminate sheet (200) through the first protective film reel (1501a, 1502a) and the second protective film reel (1501b, 1502b) and can be reused, and there is an advantage in that productivity and cost-effectiveness can be further improved.

[0053] The laminating unit (1701, 1702, 1801, 1802) may include a heater unit (1701, 1702) and a pressure roller unit (1801, 1802). More specifically, the heater unit (1701, 1702) may include a pair of first heater units (1701) and second heater units (1702) spaced apart with an electrode laminate sheet (200) therebetween. In addition, the pressure roller unit (1801, 1802) may include a pair of first pressure roller units (1801) and second pressure roller units (1802) spaced apart with an electrode laminate sheet (200) therebetween. Here, the pressure roller section (1801, 1802) may be positioned after the heater section (1701, 1702) based on the direction of movement of the electrode laminate sheet (200).

[0054] More specifically, after the electrode laminate sheet (200) is heated by passing between a pair of first heater sections (1701) and second heater sections (1702), the heated electrode laminate sheet (200) can be pressed by a pair of first pressure roller sections (1801) and second pressure roller sections (1802).

[0055] For example, a pair of first heater parts (1701) and second heater parts (1702) can heat the electrode laminate sheet (200) in a temperature range of 40 degrees Celsius or more to 150 degrees Celsius or less, and a pair of first pressure roller parts (1801) and second pressure roller parts (1802) can heat the electrode laminate sheet (200) in a temperature range of 5 Mpa (50 kgf / cm 2 ) or more to 150Mpa (1500kgf / cm) 2 ) The electrode laminate sheet (200) can be pressurized within the pressure range below.

[0056] However, it is not limited thereto, and the heater section (1701, 1702) may be omitted from the laminating section (1701, 1702, 1801, 1802), and a configuration in which a heating member, such as a heating wire, is integrated into the pressure roller section (1801, 1802) may also be included in the present embodiment.

[0057] Accordingly, in the electrode laminate manufacturing device (1000) according to the present embodiment, the electrode laminate sheet (200) is subjected to a high temperature and / or high pressure process by a laminating unit (1701, 1702, 1801, 1802), and the protective film sheet (500) having high heat resistance can prevent damage and deformation of the electrode laminate sheet (200) under high temperature and / or high pressure conditions.

[0058] Referring to FIGS. 1 and 2, in the electrode laminate sheet (200), a pair of negative electrodes (121) and positive electrodes (111) may be arranged on the same vertical line, and another pair of negative electrodes (121) and positive electrodes (111) positioned adjacent to a pair of negative electrodes (121) and positive electrodes (111) may be spaced apart from each other. For example, as shown in FIG. 2, a negative electrode tab (121t) may be formed at one end of the negative electrode (121) and protruded outwardly along the longitudinal direction of the negative electrode (121), and a positive electrode tab (111t) may be formed at the other end of the positive electrode (111) and protruded outwardly along the longitudinal direction of the positive electrode (111).

[0059] The first sealing portion (1901, 1902) can bond the first sealing region (1901s) of the electrode laminate sheet (200). Here, the first sealing region (1901s) may be a portion of the first separator sheet (141) and a portion of the second separator sheet (131) located between a pair of negative electrodes (121) and positive electrodes (111) and another pair of negative electrodes (121) and positive electrodes (111). In other words, the first sealing region (1901s) may mean a region corresponding to a region between a pair of negative electrodes (121) and positive electrodes (111) and another pair of negative electrodes (121) and positive electrodes (111), among regions where the first separator sheet (141) and the second separator sheet (131) face each other.

[0060] In particular, a protective film sheet (500) may be positioned between the first sealing portion (1901, 1902) and the electrode laminate sheet (200). More specifically, the first sealing portion (1901, 1902) may include a first upper sealing portion (1901) positioned on the upper side of the electrode laminate sheet (200) and a first lower sealing portion (1902) positioned on the lower side of the electrode laminate sheet (200).

[0061] For example, the first upper sealing portion (1901) may include a first upper main body portion (1901a) and a plurality of first upper protrusions (1901b) spaced apart from each other along the outer circumference of the first upper main body portion (1901a). Here, the plurality of first upper protrusions (1901b) may extend along the longitudinal direction of the first upper main body portion (1901a). At this time, the first upper protrusions (1901b) may press the first sealing region (1901s). In addition, the first upper sealing portion (1901) can sequentially press the first sealing region (1901s) as the first upper main body portion (1901a) rotates at a speed corresponding to the moving speed of the electrode laminate sheet (200) considering the spacing between the plurality of first upper protrusions (1901b).

[0062] The first lower sealing portion (1902) may include a first lower main body portion (1902a) and a first lower cover portion (1902b) extending along the outer circumference of the first lower main body portion (1902a). Here, the first lower cover portion (1902b) may perform pressurization for membrane sealing together with the first upper sealing portion (1901) while preventing wear of the first upper protrusion (1901b).

[0063] For example, the first sealing portion (1901, 1902) is applied to the electrode laminate sheet (200) at a temperature of 40 degrees Celsius or more and 140 degrees Celsius or less and / or at a pressure of 0.1 MPa (1 kgf / cm 2 ) or more to 0.8 MPa (8 kgf / cm 2) can be bonded between the first separator sheet (140) and the second separator sheet (130) at a pressure below.

[0064] Here, the protective film sheet (500) may be positioned between the first sealing portion (1901, 1902) and the first sealing area (1901s). For example, the protective film sheet (500) may be positioned between the first upper protrusion (1901b) and the first sealing area (1901s).

[0065] However, the shape of the first sealing portion (1901, 1902) is not limited to the configuration illustrated in FIG. 1, and any shape capable of appropriately joining the first sealing area (1901s) may be included in the present embodiment.

[0066] Accordingly, in the electrode laminate manufacturing device (1000) according to the present embodiment, the electrode laminate sheet (200) is subjected to a high temperature and / or high pressure process by the first sealing portion (1901, 1902), and the protective film sheet (500) having high heat resistance can prevent damage and deformation of the electrode laminate sheet (200) under high temperature and / or high pressure conditions.

[0067] Referring to FIG. 1, the electrode laminate manufacturing device (1000) according to the present embodiment may further include a second cutting portion (1602) positioned after the first sealing portions (1901, 1902) based on the movement direction of the electrode laminate sheet (200). Here, the second cutting portion (1602) may cut the first sealing area (1901s) to manufacture a plurality of electrode laminates (100) from the electrode laminate sheet (200). For example, the second cutting portion (1602) may cut the central portion of the first sealing area (1901s). However, for convenience of explanation, the second cutting portion (1602) is only illustrated in FIG. 1 at a position corresponding to the positive electrode sheet (110), but the present embodiment may also include a case where the second cutting portion (1602) is positioned at a position corresponding to the negative electrode sheet (120).

[0068] Accordingly, in the electrode laminate manufacturing device (1000) according to the present embodiment, since the second cutting portion (1602) is positioned after the first sealing portion (1901, 1902), cutting of the second cutting portion (1602) for the first sealing area (1901s) can be facilitated.

[0069] At this time, the second protective film reel (1501b, 1502b) may be positioned before the second cutting portion (1602). In other words, a separate protective film sheet (500) may not extend between the second cutting portion (1602) and the electrode lamination sheet (200).

[0070] Accordingly, since the second cutting section (1602) is not a high temperature and / or high pressure process, the protective film sheet (500) may not be formed at a position corresponding to the second cutting section (1602), which has the advantage of reducing costs and improving productivity.

[0071] However, in the case of the electrode laminate manufacturing device according to another embodiment of the present invention, unlike the electrode laminate manufacturing device (1000) described above, the second protective film reel (1501, 1502b) may be placed before the first sealing portion (1901, 1902). More specifically, since the laminating portions (1701, 1702, 1801, 1802) may each come into contact with the negative electrode (121) and the positive electrode (111) included in the electrode laminate sheet (200), it may be essential to place a protective film sheet (500) between the laminating portions (1701, 1702, 1801, 1802) and the electrode laminate sheet (200). In contrast, at the point where the first sealing portion (1901, 1902) comes into contact with the first separator sheet (141) and the second separator sheet (131), the protective film sheet (500) may be omitted from being placed between the first sealing portion (1901, 1902) and the electrode laminate sheet (200).

[0072] However, in the case of the electrode laminate manufacturing device (1000) described above, since a protective film sheet (500) is placed on both the first sealing portion (1901, 1902) and the laminating portion (1701, 1702, 1801, 1802), there is an advantage in that process convenience and productivity can be further improved.

[0073] The second sealing portion (1903) can bond the second sealing area (1903s) of the electrode laminate sheet (200). Here, the second sealing area (1903s) extends along the longitudinal direction of the first separator sheet (141) and the second separator sheet (131), and may be a portion of the first separator sheet (141) where the negative electrode (121) is not arranged and a portion of the second separator sheet (131) where the positive electrode (111) is not arranged. As shown in Fig. 1, the second protective film reel (1501b, 1502b) can be positioned before the second sealing portion (1903).

[0074] Fig. 3 is a cross-sectional view showing a protective film sheet included in the electrode laminate manufacturing device of Fig. 1. Fig. 4(a) shows a conventional protective film sheet, and Fig. 4(b) is a drawing showing the surface of the protective film sheet of Fig. 3.

[0075] Referring to FIGS. 3 and 4, a protective film sheet (500) according to an embodiment of the present invention is a protective film sheet (500) made of a first layer (501) including at least one selected from the group consisting of PI (Polyimide), PET (polyethylene terephthalate), PP (polypropylene), PCT (polycyclohexylenedimethylene terephthalate), and PEN (polyethylene naphthalate), and Si (silicon) laminated on the first layer. In other words, the protective film sheet (500) according to the present embodiment may include a first layer (501) including at least one selected from the group consisting of PI (polyimide), PET (polyethylene terephthalate), PP (polypropylene), PCT (polycyclohexylenedimethylene terephthalate), and PEN (polyethylene naphthalate), and a second layer (502) formed by coating Si (silicon) on the first layer. More preferably, the first layer (501) may be made of PI (Polyimide) and the second layer (502) may be made of Si (Silicon).

[0076] Referring to FIGS. 1 and 3, the second layer (502) of the protective film sheet (500) may face the electrode lamination sheet (200), and the first layer (501) of the protective film sheet (500) may face the laminating portions (1701, 1702, 1801, 1802) and the first sealing portion (1901, 1902), respectively.

[0077] The protective film sheet (500) according to the present embodiment may not be deformed at a temperature of 40 degrees Celsius or more to 150 degrees Celsius or less and a pressure of 0.1 Mpa or more to 150 Mpa or less.

[0078] More specifically, as shown in FIG. 4(b), the moisture content of the protective film sheet (500) may be 0.001 ppm or more and 5000 ppm or less. Here, the protective film sheet (500) may undergo a moisture removal process performed at a temperature of 100 degrees Celsius or more. For example, the moisture removal process may be performed by radiant heat from an IR / MICA heater. As another example, the moisture removal process may be performed by convective heat from hot air. However, the moisture removal process is not limited thereto, and any process that allows the protective film sheet (500) to have a moisture content within the above-described range may be included in the present embodiment.

[0079] Accordingly, the protective film sheet (500) according to the present embodiment has a moisture content within the above-described range, and thus has high heat resistance, while also having the advantage of being able to be reused in high temperature and / or high pressure processes.

[0080] In contrast, it can be confirmed that the conventional protective film sheet is deformed at a temperature of 140 degrees Celsius or higher and a pressure of 0.2 Mpa or higher, as shown in Fig. 4(a).

[0081] In addition, the protective film sheet (500) further includes a coating layer (not shown) formed on the outer surface of the protective film sheet (500), and the coating layer may be made of a ceramic material. For example, the ceramic material may be alumina ceramic (Al2O3). However, the ceramic material is not limited thereto, and any ceramic material that can be coated on the outer surface of the protective film sheet (500) may be included in the present embodiment.

[0082] Accordingly, the protective film sheet (500) according to the present embodiment has an additional coating layer formed on the outer surface of the protective film sheet (500), so that the protective film sheet (500) can be more effectively prevented from being deformed during the process performed by the laminating section (1701, 1702, 1801, 1802) and the first sealing section (1901, 1902), and has the advantage of being able to be reused in a high temperature and / or high pressure process.

[0083] A battery cell according to another embodiment of the present invention may include an electrode laminate manufactured by the electrode laminate manufacturing apparatus described above. In addition, the battery cells may be included in a battery module in a stacked form in multiple pieces, and one or more of the battery modules may be packaged in a pack case to form a battery pack. In addition, the battery cells may be directly packaged in a pack case in a stacked form in multiple pieces to form a battery pack, and some of the components of the battery module unit may be omitted.

[0084] The battery pack described above can be applied to various devices. These devices include electric bicycles, electric vehicles, hybrid vehicles, and other transportation vehicles. However, the present invention is not limited thereto, and can be applied to various devices that utilize battery modules and battery packs containing the same, which also fall within the scope of the present invention.

[0085]

[0086] Hereinafter, the present invention will be described through more specific examples. However, the following examples are provided to exemplify the present invention, and the scope of the present invention is not limited thereto.

[0087]

[0088] <Manufacturing Example>

[0089] A protective film sheet was manufactured including a first layer made of PI (Polyimide) with a thickness of 12 μm and a second layer coated with Si (Silicon) with a thickness of 0.01 μm or more and 10 μm or less on the first layer. Here, PI has a glass transition temperature (T) of 250 degrees Celsius. g ) and has 90% transparency.

[0090]

[0091] <Example>

[0092] Two separators were placed between a pair of protective film sheets manufactured according to the above manufacturing example, and were placed so that the second layer of each protective film sheet and the separator were in contact. Here, the separator is PE (Polyethylene) having a thickness of 15 μm.

[0093] As described above, a pair of sealing members was pressurized at a pressure of 0.2 MPa and heated to 140 degrees Celsius for the upper and lower portions of a laminate having two separators arranged between a pair of protective film sheets. Here, a pair of sealing members is configured to include a sealing tool and a cartridge heater in one piece, and a pair of sealing members is arranged such that the sealing tool and the upper and lower portions of the laminate are in contact with each other.

[0094]

[0095] <Comparative Example>

[0096] In the protective film sheet manufactured according to the above manufacturing example, it can be manufactured in the same manner as in the example, except that the first layer is PET (polyethylene terephthalate) having a thickness of 12 μm. Here, PET has a glass transition temperature (T) of 80 degrees Celsius. g ) and has 90% transparency.

[0097]

[0098] <Experimental Example 1_Checking the Appearance of the Protective Film Sheet> Whether or not there is deformation / transfer

[0099] In the laminates manufactured in the examples and comparative examples, the outer surface of the protective film sheet was enlarged and photographed, and the results are shown in FIGS. 5 and 6. FIGS. 5 and 6 are drawings showing the results for the comparative examples and examples according to Experimental Example 1. In FIGS. 5 and 6, (a) is a drawing showing the case where the number of sealings is 0, (b) is a drawing showing the case where the number of sealings is 1, and (c) is a drawing showing the case where the number of sealings is 50.

[0100] Referring to Fig. 5, it can be seen that the degree of deformation of the protective film sheet of the comparative example increases as the number of sealings gradually increases, and it can be seen that some of the separator is transferred.

[0101] In contrast, referring to FIG. 6, it can be confirmed that the protective film sheet of the embodiment has almost no deformation even when the number of sealing cycles gradually increases, and the separator is also not transferred.

[0102] Accordingly, it can be confirmed that the protective film sheet of the embodiment does not undergo thermal deformation under high temperature and high pressure conditions, unlike the comparative example, because the first layer is made of a material having a relatively high glass transition temperature. In other words, it can be confirmed that in cases where the protective film sheet of the embodiment has high heat resistance, thermal deformation under high temperature and high pressure conditions can be effectively prevented.

[0103]

[0104] <Experimental Example 2_Checking whether the membrane is sealed>

[0105] In the laminates manufactured in the examples and comparative examples, the thicknesses of the two separators were measured to confirm whether the two separators were sealed.

[0106] At this time, in the comparative example, the thickness of the two separation membranes was confirmed to be 19 um, and in the example, the thickness of the two separation membranes was confirmed to be 12.5 um.

[0107] Accordingly, it can be confirmed that the protective film sheet of the embodiment seals the two separators more effectively than the comparative example. In other words, it can be confirmed that the protective film sheet of the embodiment has high heat resistance, unlike the comparative example, while also having effective sealing performance.

[0108] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims also fall within the scope of the present invention.

Claims

1. A protective film sheet comprising a first layer comprising at least one selected from the group consisting of PI (Polyimide), PET (polyethylene terephthalate), PP (polypropylene), PCT (polycyclohexylenedimethylene terephthalate), and PEN (polyethylene naphthalate) and a second layer made of Si (silicon) laminated on the first layer, A protective film sheet having a moisture content of 0.001 ppm or more and 5000 ppm or less, or further comprising a coating layer made of a ceramic material on the outer surface of the protective film sheet.

2. In paragraph 1, The above protective film sheet is a protective film sheet that does not deform even at a temperature of 40 degrees Celsius or more and 150 degrees Celsius or less and a pressure of 0.1 Mpa or more and 150 Mpa or less.

3. In paragraph 2, A protective film sheet having a moisture content of 0.001 ppm or more and 5000 ppm or less, and including a coating layer made of a ceramic material on the outer surface of the protective film sheet.

4. An electrode laminate manufacturing device that manufactures an electrode laminate including the protective film sheet of paragraph 1, in which a first separator, a negative electrode, a second separator, and an anode are sequentially laminated, A laminating unit for bonding electrode laminate sheets in which a plurality of the cathodes are arranged spaced apart from each other on a first separator sheet and a plurality of the anodes are arranged spaced apart from each other on a second separator sheet; and It includes a first sealing portion that connects the first separator sheet and the second separator sheet to each other, An electrode laminate manufacturing device wherein the protective film sheet extends along the moving direction of the electrode laminate sheet and is positioned between the laminating portion and the electrode laminate sheet and between the first sealing portion and the electrode laminate sheet.

5. In paragraph 4, It includes a first protective film reel and a second protective film reel spaced apart with the laminating part and the sealing part interposed therebetween, The above protective film sheet is unwound from the first protective film reel and then wound from the second protective film reel, An electrode laminate manufacturing device in which the protective film sheet wound on the second protective film reel is reused.

6. In paragraph 5, An electrode laminate manufacturing device in which the protective film sheet wound on the second protective film reel is re-wound on the first protective film reel.

7. In paragraph 5, An electrode laminate manufacturing device in which the second protective film reel on which the protective film sheet is wound is replaced with the first protective film reel on which the protective film sheet is already wound.

8. In paragraph 4, The second layer of the above protective film sheet faces the electrode laminate sheet, An electrode laminate manufacturing device in which the first layer of the above protective film sheet faces the first sealing portion.

9. In paragraph 4, Further comprising a reel from which the first separator sheet, the negative electrode sheet, the second separator sheet, and the positive electrode sheet are each unwound, It further includes a first cutting section positioned before the laminating section based on the movement direction of the electrode laminated sheet, and cutting the negative electrode sheet and the positive electrode sheet, respectively. The first cutting section cuts the cathode from the cathode sheet and the anode from the anode sheet, An electrode laminate manufacturing device in which the first protective film reel is positioned after the first cutting section.

10. In paragraph 4, In the above electrode laminated sheet, A pair of the above cathodes and anodes are arranged on the same vertical line, An electrode laminate manufacturing device, wherein the pair of the cathodes and the anodes and the other pair of the cathodes and the anodes are positioned adjacent to each other and are spaced apart from each other.

11. In paragraph 10, The first sealing portion bonds the first sealing area of ​​the electrode laminate sheet, The first sealing region is the first separator sheet portion and the second separator sheet portion located between the pair of the cathodes and the anodes and the other pair of the cathodes and the anodes, An electrode laminate manufacturing device in which the protective film sheet is positioned between the first sealing portion and the electrode laminate sheet.

12. In paragraph 11, The first sealing portion includes a first upper sealing portion located on the upper side of the electrode laminate sheet and a first lower sealing portion located on the lower side of the electrode laminate sheet, The first upper sealing portion includes a first upper main body portion and a plurality of first upper protrusions spaced apart from each other along the outer surface of the first upper main body portion, An electrode laminate manufacturing device in which the plurality of first upper protrusions extend along the longitudinal direction of the first upper main body.

13. In paragraph 12, The above protective film sheet is located between the first upper protrusion and the first sealing area, An electrode laminate manufacturing device in which the first upper protrusion presses the first sealing area.

14. In paragraph 11, It further includes a second cutting section positioned after the first sealing section based on the movement direction of the electrode laminate sheet, and cutting the first sealing area to manufacture a plurality of electrode laminates. An electrode laminate manufacturing device in which the second protective film reel is positioned before the second cutting section.

15. In paragraph 10, Further comprising a second sealing portion for bonding the second sealing area of ​​the electrode laminate sheet, The second sealing region extends along the longitudinal direction of the first separator sheet and the second separator sheet, and is a portion of the first separator sheet where the cathode is not arranged and a portion of the second separator sheet where the anode is not arranged. An electrode laminate manufacturing device in which the second protective film reel is positioned before the second sealing portion.

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