KR20220071766A - Flexible printed circuit board and connecting member for battery cell module having the same - Google Patents

Abstract

The present invention relates to a flexible printed circuit board and a battery cell module connection member including the same, and more particularly, to a flexible printed circuit board having excellent ductility, high degree of freedom in circuit wiring design, lightweightness, and excellent productivity, and a battery cell module connection member including the same.

Description

Flexible printed circuit board and battery cell module connection member including same

The present invention relates to a flexible printed circuit board and a battery cell module connection member including the same, and to a flexible printed circuit board having excellent ductility and a high degree of freedom in designing circuit wiring, light weight and excellent productivity, and a battery cell including the same It relates to a module connection member.

Secondary batteries are widely used in mobile devices, auxiliary power devices, and the like. In addition, secondary batteries are attracting attention as a main power source for electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, etc. presented as an alternative to solve various problems such as air pollution of conventional gasoline or diesel vehicles.

However, due to the need for high-output, large-capacity batteries in electric vehicles, battery cell modules in which a plurality of battery cells are stacked and then electrically connected in series and in parallel are used.

A bus bar module is used to connect the battery cells in series or in parallel. The busbar module is an aggregate of busbars, and has a structure in which each busbar is electrically connected to a terminal portion of a flexible flat cable (FFC). A battery cell module and a peripheral device (eg, an ECU of a vehicle) are connected through such a bus bar module, so that overvoltage and overcurrent of the battery cell can be controlled. However, since the FFC of the busbar module can only be wired in a straight line, there is a limitation in designing it with various types of wiring. In addition, since the FFC uses too thin a conducting wire, there is a fear that the conducting wire may boil during the production process, and the applicable width and thickness of the conducting wire are also limited.

Accordingly, conventionally, a flexible printed circuit board (FPCB) has been used instead of an FFC. Since a flexible printed circuit board forms a circuit pattern through an etching process, it has a higher degree of freedom in circuit design compared to an FFC and can also form a narrow circuit. In such a flexible printed circuit board, a coverlay film is attached to the circuit wiring in order to protect the circuit.

However, conventionally, a hot press device was used for attaching the coverlay film. For this reason, in manufacturing a long flexible printed circuit board such as FFC, circuit wiring cannot be covered with only one coverlay film, so a plurality of coverlay films are connected to each other and used to manufacture a printed circuit board. As a result, heat resistance and vibration resistance were lowered at the overlapping portion of the coverlay film, and the product was warped. In addition, in the prior art, it was attempted to manufacture a large-sized printed circuit board using a large-sized hot press device. However, when a large-size flexible printed circuit board is manufactured using a large-sized hot press device, pressure unevenness occurred inside the product because it is a cotton press, which resulted in quality deterioration or thickness deviation, and also the large-size flexible printed circuit board. When the printed circuit board was laminated, there were also defects due to handling.

As such, there has been a limitation in manufacturing a flexible printed circuit board having a long length or a large size in the related art.

An object of the present invention is to provide a flexible printed circuit board capable of freely designing a desired length and circuit pattern, realizing a curved surface, and having excellent insulation and heat resistance, and a battery cell module connecting member including the same.

In order to achieve the above object, the present invention is a first insulating layer; a plurality of circuit wirings disposed on one surface of the first insulating layer and having a terminal portion electrically connected to a bus-bar at one end; a second insulating layer covering the plurality of circuit wirings and continuously formed along one direction of the first insulating layer; and a first adhesive layer interposed between the first insulating layer and the second insulating layer, wherein the flexible printed circuit board has one direction along a bonding surface of the first insulating layer and the second insulating layer. To provide a flexible printed circuit board that is formed to extend and has a thickness deviation of 1 to 5 μm.

According to an example, the flexible printed circuit board may further include a second adhesive layer interposed between the first insulating layer and the plurality of circuit wires.

According to another example, the flexible printed circuit board may include a plurality of second circuit wires disposed on the other surface of the first insulating layer and having a second terminal part electrically connected to the bus bar at one end; a third insulating layer covering the plurality of second circuit wirings and continuously formed along one direction of the first insulating layer; and a third adhesive layer interposed between the first insulating layer and the third insulating layer. In this case, a second adhesive layer interposed between the first insulating layer and the plurality of circuit wiring; and/or a fourth adhesive layer interposed between the first insulating layer and the plurality of second circuit wires.

In addition, the present invention provides a battery cell module connecting member including the above-described flexible printed circuit board.

According to an example, the battery cell module connection member may further include a bus bar positioned on the same plane as a contact surface between the second insulating layer and the circuit wiring and electrically connected to each terminal of the flexible printed circuit board.

According to another example, the battery cell module connecting member is positioned on the same plane as the contact surface between the third insulating layer and the second circuit wiring, and a second bus bar electrically connected to each second terminal of the flexible printed circuit board. may include more.

The flexible printed circuit board of the present invention can be freely designed to a desired length beyond the limit of the length, can be curved, and has excellent insulation and heat resistance. It can be used as a terminal connecting member.

1 is a perspective view schematically showing a flexible printed circuit board according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along line AA of FIG. 1 .
3 is a perspective view schematically illustrating a flexible printed circuit board according to a second embodiment of the present invention.
4 is a cross-sectional view taken along line AA of FIG. 3 .
5 is a perspective view schematically illustrating a flexible printed circuit board according to a third embodiment of the present invention.
6 is a cross-sectional view taken along line AA of FIG. 5 .
7 is a perspective view schematically illustrating a flexible printed circuit board according to a fourth embodiment of the present invention.
FIG. 8 is a cross-sectional view taken along line AA of FIG. 7 .
9 is a plan view of a battery cell module connecting member according to the present invention.
10 is a cross-sectional view taken along line BB of FIG. 9 , and is a perspective view schematically illustrating a battery cell module connection member including the flexible printed circuit board according to the first embodiment.
11 is a plan photograph of an open surface portion of a terminal portion of a circuit wiring in a flexible printed circuit board manufactured in Example 1. FIG.
12 is a plan photograph of an open surface portion of a terminal portion of a circuit wiring in a flexible printed circuit board manufactured in Comparative Example 1. Referring to FIG.
13(a) is a photomicrograph showing a cross-section of the flexible printed circuit board manufactured in Example 1, and FIG. 13(b) is a photomicrograph showing a cross-section of the flexible printed circuit board manufactured in Comparative Example 1. Referring to FIG.

Hereinafter, with reference to the accompanying drawings, the embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

It is noted that the drawings are schematic and not drawn to scale. Relative dimensions and proportions of parts in the drawings are shown exaggerated or reduced in size for clarity and convenience in the drawings, and any dimensions are illustrative only and not limiting. And the same reference numerals are used to denote like features to the same structure, element, or part appearing in two or more drawings.

The embodiment of the present invention specifically represents an ideal embodiment of the present invention. As a result, various modifications of the diagram are expected. Accordingly, the embodiment is not limited to a specific shape of the illustrated area, and includes, for example, a shape modification by manufacturing.

1 is a perspective view schematically showing a flexible printed circuit board according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1 . 3 is a perspective view schematically showing a flexible printed circuit board according to a second embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3 . 5 is a perspective view schematically showing a flexible printed circuit board according to a third embodiment of the present invention, and FIG. 6 is a cross-sectional view taken along line A-A of FIG. 5 . 7 is a perspective view schematically showing a flexible printed circuit board according to a fourth embodiment of the present invention, and FIG. 8 is a cross-sectional view taken along line A-A of FIG. 8 .

1 to 8 , the flexible printed circuit board 100A, 100B, 100C, 100D according to the present invention is a terminal connecting member (eg, a battery cell module) for connecting terminals of adjacent battery cells in a battery cell module. connecting member, etc.), the first insulating layer 10 and the second insulating layer 30 disposed to face each other, a plurality of circuit wirings 20 sequentially disposed therebetween, and the first adhesive layer (40). Optionally, the flexible printed circuit boards 100B and 100D according to the present invention may further include a second adhesive layer 50 disposed between the first insulating layer 10 and the plurality of circuit wires 20 . . In addition, the flexible printed circuit board (100C, 100D) according to the present invention includes a plurality of second circuit wires (60) disposed on the other surface of the first insulating layer (10); a third insulating layer 70 covering the plurality of second circuit wirings 60; and a third adhesive layer 80 interposed between the first insulating layer and the third insulating layer. In addition, the flexible printed circuit board 100D according to the present invention may further include a fourth adhesive layer 90 interposed between the first insulating layer 10 and the plurality of second circuit wires 60 . However, the flexible printed circuit board 100 of the present invention is formed extending in one direction [eg, Machine Direction (MD)] along the bonding surface of the first insulating layer 10 and the second insulating layer 30, the thickness The deviation ranges from 1 to 5 μm.

Specifically, the flexible printed circuit board (100A, 100B, 100C, 100D) of the present invention includes a plurality of circuit wires 20, a first adhesive layer 40 and a second insulating layer ( 30) are sequentially stacked and integrated, and are in the form of rolls extending in one direction (eg, MD). The flexible printed circuit boards 100A, 100B, 100C, and 100D of the present invention have a first laminate in which a plurality of circuit wires 20 are laminated on a first insulating layer 10 and a second insulating layer 30 on the A second laminate (eg, a coverlay film) on which the first adhesive layer 40 is laminated is laminated to each other through a roll-to-roll continuous automatic method to extend in one direction (eg, MD) It is manufactured in roll form. That is, when the second laminate of the present invention is disposed on the plurality of circuit wirings 20 of the first laminate, the circuit wiring 20 ) can be stacked on Therefore, in the present invention, unlike the prior art, a second laminate having a length corresponding to the length of the first laminate is laminated on the first laminate without overlapping and connecting the ends of the plurality of second laminates in contact with each other. to protect the circuit wiring 20 . Therefore, unlike the prior art, the second insulating layer 30 and the first adhesive layer 40 of the present invention are continuously formed in one direction (eg, MD) without overlapping portions every predetermined length, so that heat resistance due to overlapping portions, There is no deterioration in vibration resistance or distortion of the product. In addition, according to the present invention, the second laminate of the second insulating layer 30 and the first adhesive layer 40 continuously supplied is on the plurality of first circuit wirings 20 by a pair of heating rollers. By the line lamination, unlike the face lamination by a press machine, it is continuously pressed with a uniform line contact pressure (line contact pressure). For this reason, the second laminate of the second insulating layer 30 and the first adhesive layer 40 is uniformly formed on the surface of the first insulating layer 10 on which the plurality of circuit wirings 20 are formed, even if the size is large. It can be arranged in thickness.

In this way, the flexible printed circuit boards 100A, 100B, 100C, and 100D of the present invention are formed to extend in one direction along the bonding surface of the first insulating layer 10 and the second insulating layer 30, and the thickness deviation is By being controlled within the range of 1 to 5 μm, uniformity of properties in the substrate, such as heat resistance, voltage resistance, long-term reliability, etc., can be secured, so that quality deviation within the substrate can be minimized. In addition, the flexible printed circuit board (100A, 100B, 100C, 100D) of the present invention can be freely designed to a desired length beyond the limit of the length, and the circuit pattern can be freely designed, curved, and has excellent insulation and heat resistance Therefore, it may be used as a terminal connecting member for connecting terminal portions of adjacent battery cells in the battery cell module.

Hereinafter, a flexible printed circuit board 100A according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2 .

(1) first insulating layer

In the flexible printed circuit board 100A according to the first embodiment of the present invention, the first insulating layer 10 is laminated with the second insulating layer 30 by the first adhesive layer 40 to form a plurality of circuit wirings ( 20) is protected.

The first insulating layer 10 is a plastic film in the form of a thin film made of a flexible material having flexible properties in the art, and is not particularly limited as long as it is capable of realizing a curved surface and is an insulating and heat-resistant polymer film.

Specifically, non-limiting examples of the first insulating layer 10 include a polyimide (PI) film, a polyethersulphone (PES) film, a polyacrylate (PAR) film, and a polyetherimide (PEI) film. ) film, polyethylene naphthalate (PEN) film, polyethylene terephthalate (PET) film, polyphenylene sulfide (PPS, polyphenylene sulfide) film, polyallylate film, polycarbonate (PC) films, cellulose triacetate (TAC) films, cellulose acetate propionate (CAP) films, poly(arylene ether sulfone) films, and the like. Such a polymer film may be transparent or translucent, or may be colored or uncolored, and may be appropriately selected according to the use. According to one example, the flexible substrate 100 may be a polyimide substrate. In this case, the first insulating layer 10 may be a single layer or a plurality of layers, and in the case of a plurality of layers, may have a structure in which two or more different types of films are stacked.

The first insulating layer 10 is continuously formed in one direction, and may be, for example, a roll-shaped film continuous in one direction (eg, longitudinal direction, MD). Accordingly, in the first insulating layer 10 , the ratio (L _MD /L _TD ) of the length (L _MD ) in the longitudinal direction (eg, MD) to the length (L _TD ) in the width direction (eg, TD) is about 1 to 150. In this case, the length (L _MD ) in the longitudinal direction may be about 500 mm or more and about 500 to 3,000 mm, and the length (L _TD ) in the width direction may be about 20 mm or more, about 20 to 500 mm.

In addition, the thickness of the first insulating layer 10 is not particularly limited, and may be, for example, in the range of about 12 to 50 μm.

(2) Multiple circuit wiring

In the flexible printed circuit board 100A according to the first embodiment of the present invention, the plurality of circuit wires 20 are disposed on one surface of the first insulating layer 10 , and the plurality of circuit wires 20 are predetermined It is patterned in a predetermined shape having a width and thickness of . For example, the plurality of circuit wirings 20 are linear patterns extending along one direction of the first insulating layer 10 , and each pattern is spaced apart from each other at regular intervals and formed in parallel, or in one direction and Alternatively, it may have a structure in which predetermined patterns extending in an intersecting direction are continuously arranged in one direction. According to an example, each of the plurality of circuit wirings 20 is disposed to be spaced apart from each other in the width direction of the first insulating layer 10 , and each circuit wiring 20 is arranged to extend along the longitudinal direction of the first insulating layer 10 . can be

The material of the plurality of circuit wirings 20 is not particularly limited as long as it is a conductive material generally used in the art, specifically, a conductive metal. Non-limiting examples of the conductive material include chromium (Cr), nickel (Ni), zinc (Zn), molybdenum (Mo), tungsten (W), cobalt (Co), lead (Pb), silver (Ag), tantalum (Ta), copper (Cu), aluminum (Al), manganese (Mn), iron (Fe), titanium (Ti), tin (Sn), steel (Steel), zinc (Zn) and vanadium (V), palladium (Pd) and the like, and these may be used alone or in the form of a mixture or alloy of two or more thereof. According to an example, the plurality of circuit wirings 20 may be copper wirings.

Each of these circuit wirings 20 includes a terminal part 21 electrically connected to a bus-bar at one end, and an internal circuit part 22 extending to one side of the terminal part 21 .

The terminal part 21 is a portion located at one end of the circuit wiring 20 , non-overlapping with the second insulating layer 30 , and is electrically connected to the bus bar. According to one example, the terminal part 21 is in direct surface contact with the bus bar. As a result, connection failure or a short circuit between the terminal unit 21 and the bus bar is minimized, so that connection stability can be improved, and contact resistance can be lowered.

A method of contacting the bus bar to the terminal unit 21 is not particularly limited as long as it is generally known in the art, and for example, reflow soldering through solder paste, soldering, laser soldering, ultrasonic welding, direct bolting, or the like.

In addition, the terminal part 21 includes an open surface with an exposed surface, and an adhesive bead layer 41 having a directionality in the machine direction MD of the flexible printed circuit board is formed on one side of the open surface.

Specifically, in manufacturing the flexible printed circuit board 100A by the roll-to-roll method, the coverlay film including the first adhesive layer 40 and the second insulating layer 30 is the circuit wiring 20 disposed therein. The first insulating layer 10 is laminated with a pair of heating rollers. At this time, the first adhesive layer 40 is melted by the heat of the heating roller part. Unlike the face lamination by the hot press process, the molten adhesive flows only in the machine direction (MD) side, which is the process progress direction, by the pressure of the heating roller part have a gender Accordingly, a part of the molten adhesive flows onto the open surface of the exposed terminal part 20 by not overlapping the second insulating layer 30, and when a part of the adhesive that has flowed in this way is cured, as shown in FIG. An adhesive bead layer 41 having directionality in the machine direction of the flexible printed circuit board is formed on one side. In this case, the adhesive bead layer 41 is formed to extend from the first adhesive layer 40 . In addition, as in the second embodiment, when the second adhesive layer 50 is positioned between the first insulating layer 10 and the plurality of circuit wirings 20, the adhesive bead layer 41 is a first adhesive layer ( 40) as well as being formed extending from the second adhesive layer 50, the components of the first adhesive layer 40 and the second adhesive layer 50 are mixed. As such, in the terminal part 21 of the present invention, unlike the surface lamination by the hot press process, since the adhesive bead layer 41 having directionality is formed on the open surface of the terminal part 21, the terminal part to which the bus bar can be contacted. The area of (21) is increased to enlarge the electrical path, and thus the electrical resistance can be reduced.

The circuit wiring 20 of the present invention may further include a connector part 23 positioned at the other end and electrically connected to the external circuit board. As shown in FIG. 1 , the connector part 23 has a surface exposed to the outside by not overlapping the second insulating layer 30 . As the battery cell module is electrically connected to an external device (eg, automobile ECU, etc.) through the connector unit 23, the voltage, current, and temperature of the battery cell module are monitored in real time, and excessive charging or discharging is prevented in advance. Thus, the safety and reliability of the battery cell module can be improved.

The width and thickness of the circuit wiring 20 are not particularly limited, and for example, the width may be in the range of about 30 μm or more, specifically, about 30 to 100 μm, and the thickness may be in the range of about 6 to 70 μm.

(3) second insulating layer

In the flexible printed circuit board 100A of the present invention, the second insulating layer 30 covers the plurality of circuit wirings 20 , and is laminated with the first insulating layer 10 to provide a plurality of circuit wirings 20 . to protect In addition, the second insulating layer 30 also serves as a support for forming the first adhesive layer 40 when the flexible printed circuit board is manufactured.

The second insulating layer 30 usable in the present invention may be a conventional polymer film known in the art, specifically, an insulating polymer film, and non-limiting examples thereof include a polyethylene terephthalate (PET) film, polybutylene tere. Phthalate film, polyethylene naphthalate film, polyethylene film, polypropylene film, cellophane, diacetyl cellulose film, triacetyl cellulose film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene- Vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyetheretherketone film, polyethersulfone film, polyetherimide film, polyimide film, fluororesin film, There are polyamide films, acrylic resin films, norbornene-based resin films, and cycloolefin resin films. The polymer film may be transparent or translucent, and may be colored or uncolored, but is appropriately selected depending on the use. According to an example, the second insulating layer 30 may be a polyimide (PI) film, a polyethylene terephthalate (PET) film, a polyethylene naphthalate (PEN) film, a polyphenylene sulfide (PPS) film, or a polyetheretherketone (PEEK) film. , it may be at least one selected from the group consisting of a polyester sulfone film, an aromatic polyamide film, a polycarbonate film, and a polyarylate film.

The second insulating layer 30 is continuously formed along one direction of the first insulating layer 10 , and may be, for example, a roll-shaped film continuous in the longitudinal direction (eg, MD).

Specifically, the second insulating layer 30 of the present invention is not supplied in a state cut to a predetermined size when manufacturing a flexible printed circuit board, but in one direction (eg, longitudinal direction, MD) through a roll-to-roll automatic continuous method. It is continuously supplied on the plurality of circuit wirings 20 in the form of a continuous roll along the line and is laminated to the first insulating layer 10 by the first adhesive layer 40 . That is, unlike the related art, the second insulating layer 30 may be continuously formed in one direction without overlapping portions every predetermined length. Accordingly, in the second insulating layer 30 , a ratio (L _MD /L _TD ) of a length (L _MD ) in a longitudinal direction (eg, MD) to a length (L _TD ) in a width direction (eg, TD) is about 1 to 150. At this time, the second insulating layer 30 may have a length (L _MD ) in the longitudinal direction of about 500 mm or more and about 500 to 3,000 mm, and a length (L _TD ) in the width direction of about 20 mm or more, about 20 ~ It may be 500 mm.

In addition, as described above, when the second insulating layer 30 is continuously formed without overlapping portions to cover the plurality of circuit wirings 20 , the thickness of the second insulating layer 20 and the first adhesive layer 40 is reduced. The combined total thickness is uniform. For this reason, the flexible printed circuit board according to the present invention may have a thickness deviation of about 1 to 5 μm, unlike a conventional flexible printed circuit board manufactured through a hot press process. Here, the thickness deviation refers to the difference between the maximum thickness and the minimum thickness after measuring the thickness of a flexible printed circuit board (500 mmX500 mm) at 25 mm intervals for a total of 100 points. In this case, the deviation of the total thickness of the sum of the thicknesses of the second insulating layer 20 and the first adhesive layer 40 may be in the range of about 1 to 5 μm.

The thickness of the second insulating layer 30 is not particularly limited, and may be, for example, in the range of about 12 to 50 μm.

(4) first adhesive layer

In the flexible printed circuit board 100A of the present invention, the first adhesive layer 40 is interposed between the first insulating layer 10 and the second insulating layer 30, through which the second insulating layer 30 It is laminated to the first insulating layer (10). In this case, the second insulating layer 30 may be in close contact with the plurality of circuit wires 20 to protect the plurality of circuit wires 20 . Also, the first adhesive layer 40 may be interposed between the plurality of circuit wires 20 and the second insulating layer 30 .

The first adhesive layer 40 may use a conventional adhesive or pressure-sensitive adhesive known in the art, and specifically may be a thermosetting adhesive. The first adhesive layer 40 may be any one of an epoxy-based, polyimide-based, polyamide-imide-based, polyamic acid-based, polyphenylene oxide (PPO)-based, and acrylic adhesive.

The thickness of the first adhesive layer 40 is not particularly limited, and may be, for example, about 12 to 100 μm.

The above-described flexible printed circuit board 100A according to the first embodiment of the present invention can be freely designed to a desired length beyond the limit of the length, can be curved, and has excellent insulation and heat resistance, so a battery cell module It can be used as a terminal connecting member for connecting terminal parts of neighboring battery cells. In addition, it can be applied to all uses to which the conventional flexible printed circuit board is applied.

Hereinafter, a flexible printed circuit board 100B according to a second embodiment of the present invention will be described with reference to FIGS. 3 and 4 .

As shown in Figs. 3 and 4, the flexible printed circuit board 100B according to the second embodiment of the present invention includes a first insulating layer 10; a plurality of circuit wirings (20) disposed on one surface of the first insulating layer (10) and having a terminal part (21) electrically connected to a bus bar at one end; a second insulating layer 30 covering the circuit wiring 20 and continuously formed along one direction of the first insulating layer 10; a first adhesive layer 40 interposed between the first insulating layer 10 and the second insulating layer 30; and a second adhesive layer 50 interposed between the first insulating layer 10 and the circuit wiring 20 . However, the flexible printed circuit board 100B of the present invention is formed to extend in one direction [eg, MD] along the bonding surface of the first insulating layer 10 and the second insulating layer 30, and the thickness deviation is about 1 to 5 μm.

Descriptions of the first insulating layer 10 , the plurality of circuit wirings 20 , the second insulating layer 30 , and the first adhesive layer 40 are omitted since they are the same as those described in the first embodiment, respectively.

The second adhesive layer 50 is disposed on the first insulating layer 10 to adhere the plurality of first circuit wires 20 to the first insulating layer 10 .

The second adhesive layer 50 may be the same as or different from the first adhesive layer 40 , and a conventional adhesive or pressure-sensitive adhesive known in the art may be used, and specifically may be a thermosetting adhesive. Specific examples of the second adhesive layer 50 may be any one of an epoxy-based adhesive, a polyimide-based adhesive, a polyamide-imide-based adhesive, a polyamic acid-based adhesive, a polyphenylene oxide (PPO)-based adhesive, and an acrylic adhesive.

In addition, the thickness of the second adhesive layer 50 is not particularly limited, and may be, for example, in the range of about 1 to 50 μm.

Hereinafter, a flexible printed circuit board 100C according to a third embodiment of the present invention will be described with reference to FIGS. 5 and 6 .

A flexible printed circuit board 100C according to a third embodiment of the present invention includes, as shown in FIGS. 5 and 6 , a first insulating layer 10; A plurality of circuit wirings (hereinafter, 'first circuit wirings') disposed on one surface of the first insulating layer 10 and having a terminal unit (hereinafter, 'first terminal unit') 21 electrically connected to the bus bar at one end ')(20); a second insulating layer 30 covering the first circuit wiring 20 and continuously formed along one direction of the first insulating layer 10; a first adhesive layer 40 interposed between the first insulating layer 10 and the second insulating layer 30; a plurality of second circuit wirings (60) disposed on the other surface of the first insulating layer (10) and having a second terminal portion electrically connected to a bus bar at one end; a third insulating layer (70) covering the plurality of second circuit wirings (60) and continuously formed along one direction of the first insulating layer (10); and a third adhesive layer 80 interposed between the first insulating layer 10 and the third insulating layer 70 . However, the flexible printed circuit board 100C of the present invention is formed to extend in one direction [eg, MD] along the bonding surface of the first insulating layer 10 and the second insulating layer 30, and the thickness deviation is about 1 to 5 μm.

Since the descriptions of the first insulating layer 10, the plurality of circuit wirings 20, the second insulating layer 30, and the first adhesive layer 40 are the same as those described in the first embodiment, respectively, they are omitted.

The plurality of second circuit wirings 60 are disposed on the other surface of the first insulating layer 10 , and similarly to the plurality of first circuit wirings 20 , the plurality of second circuit wirings 60 have a predetermined width. It is patterned in a predetermined shape having a thickness and thickness. For example, the plurality of second circuit wirings 60 are linear patterns extending along one direction of the first insulating layer 10 , and each of the patterns may be spaced apart from each other at regular intervals and formed in parallel, or It may have a structure in which predetermined patterns extending in a direction and/or crossing directions are continuously arranged in one direction. According to an example, each of the plurality of second circuit wirings 60 is spaced apart from each other in the width direction of the first insulating layer 10 , and each second circuit wiring 60 has a length of the first insulating layer 10 . It may be arranged to extend along the direction.

The material of the second circuit wiring 60 may be the same as or different from that of the first circuit wiring 20 , and is not particularly limited as long as it is a conductive material generally used in the art, specifically, a conductive metal. Since the example of such a conductive material is the same as that described in 1st Embodiment, it is abbreviate|omitted.

Each of the second circuit wires 60 includes a second terminal part (not shown) electrically connected to the bus bar at one end, and a second internal circuit part (not shown) extending to one side of the second terminal part.

The second terminal portion is a portion located at one end of the second circuit wiring 60 , does not overlap the third insulating layer 70 , and is electrically connected to the bus bar. According to an example, the second terminal portion is in direct surface contact with the bus bar. Accordingly, connection stability between the second terminal unit and the bus bar may be improved, and contact resistance may be lowered.

Also, like the first terminal part 21 , the second terminal part includes an open surface with an exposed surface, and an adhesive bead layer having directionality in the machine direction is formed on one side of the open surface. Since the description of such an adhesive bead layer is the same as that described in the first embodiment, it is omitted.

In addition, the second circuit wiring 60 may further include a second connector part (not shown) located at the other end and electrically connected to the external circuit board. The description of this second connector part is omitted because it is the same as described in the first connector part part of the first embodiment.

The width and thickness of the second circuit wiring 60 are not particularly limited, and for example, the width may be in the range of about 30 μm or more, specifically, about 30 to 100 μm, and the thickness may be in the range of about 6 to 70 μm.

In the flexible printed circuit board 100C of the present invention, the third insulating layer 70 covers the plurality of second circuit wires 60 , and is laminated with the first insulating layer 10 to form a plurality of second circuits. The wiring 60 is protected.

The third insulating layer 70 usable in the present invention may be a conventional polymer film known in the art, specifically, an insulating polymer film. In this case, the third insulating layer 70 may be the same as or different from the second insulating layer 30 . Since the example of the said polymer film is the same as that described in the 2nd insulating layer part of 1st Embodiment, it is abbreviate|omitted.

The third insulating layer 70 is continuously formed in one direction, and may be, for example, a roll-shaped film continuous in the longitudinal direction (eg, MD). Like the second insulating layer 30 , the third insulating layer 70 is continuously supplied on the plurality of second circuit wirings 60 in the form of a roll continuous in one direction without cutting during the manufacturing of the flexible printed circuit board. By being laminated to the first insulating layer 10 by the second adhesive layer 80 , it is possible to cover the plurality of second circuit wirings 60 without overlapping portions every predetermined length. Accordingly, in the third insulating layer 70 , the ratio (L _MD /L _TD ) of the length (L _MD ) in the longitudinal direction (eg, MD) to the length (L _TD ) in the width direction (eg, TD) is about 1 to 150. In this case, the third insulating layer 70 may have a length (L _MD ) of about 500 mm or more and about 500 to 3,000 mm in the longitudinal direction, and a length (L _TD ) of about 20 mm or more, about 20 ~ It may be 500 mm.

In addition, when not only the second insulating layer 30 but also the third insulating layer 70 are continuously formed without overlapping portions to cover the plurality of second circuit wirings 60 , the second insulating layer 20 and the first adhesive layer Since the total thickness of 40 and the total thickness of the third insulating layer 70 and the third adhesive layer 80 are all uniform, the thickness deviation of the flexible printed circuit board according to the present invention may be in the range of about 1 to 5 μm. have. Here, the thickness deviation refers to the difference between the maximum thickness and the minimum thickness after measuring the thickness of a flexible printed circuit board (500 mmX500 mm) at 25 mm intervals for a total of 100 points. In this case, the deviation of the total thickness of the sum of the thicknesses of the third insulating layer 70 and the third adhesive layer 80 may be in the range of about 1 to 5 μm.

The thickness of the third insulating layer 70 is not particularly limited, and may be, for example, in the range of about 12 to 50 μm.

In the flexible printed circuit board 100C of the present invention, the third adhesive layer 80 is interposed between the first insulating layer 10 and the third insulating layer 70, and the first insulating layer 10 and the 3 The insulating layer 70 is laminated. In this case, the third insulating layer 70 may be in close contact with the plurality of second circuit wirings 60 to protect the circuit wirings.

The third adhesive layer 80 may be the same as or different from the first adhesive layer 40 . Since it is the same as what was described in the 1st adhesive bond layer part of 1st Embodiment, description about this 3rd adhesive bond layer is abbreviate|omitted.

Hereinafter, a flexible printed circuit board 100D according to a fourth embodiment of the present invention will be described with reference to FIGS. 7 and 8 .

As shown in FIGS. 7 and 8 , a flexible printed circuit board 100D according to a fourth embodiment of the present invention includes a first insulating layer 10; A plurality of circuit wirings (hereinafter, 'first circuit wirings') disposed on one surface of the first insulating layer 10 and having a terminal unit (hereinafter, 'first terminal unit') 21 electrically connected to the bus bar at one end ')(20); a second insulating layer 30 covering the first circuit wiring 20 and continuously formed along one direction of the first insulating layer 10; a first adhesive layer 40 interposed between the first insulating layer 10 and the second insulating layer 30; a second adhesive layer (50) interposed between the first insulating layer (10) and the plurality of first circuit wires (20); a plurality of second circuit wirings (60) disposed on the other surface of the first insulating layer (10) and having a second terminal portion electrically connected to a bus bar at one end; a third insulating layer (70) covering the plurality of second circuit wirings (60) and continuously formed along one direction of the first insulating layer (10); a third adhesive layer 80 interposed between the first insulating layer 10 and the third insulating layer 70; and a fourth adhesive layer 90 interposed between the first insulating layer 10 and the plurality of second circuit wires 60 . In this case, any one of the second insulating layer 30 and the fourth adhesive layer 90 may be omitted. However, the flexible printed circuit board 100D of the present invention is formed to extend in one direction [eg, MD] along the bonding surface of the first insulating layer 10 and the second insulating layer 30, and the thickness deviation is about 1 to 5 μm.

Descriptions of the first insulating layer 10, the plurality of circuit wirings 20, the second insulating layer 30, and the first adhesive layer 40 are the same as those described in the first embodiment, respectively, and the second adhesive layer The description of (50) is the same as that described in the second embodiment, and the description of the plurality of second circuit wirings 60, the third insulating layer 70, and the third adhesive layer 80 is the third embodiment, respectively. Since it is the same as what was described in the form, it abbreviate|omits.

The fourth adhesive layer 90 is disposed on the first insulating layer 10 to bond the plurality of second circuit wires 60 to the first insulating layer 10 . The fourth adhesive layer 90 may be the same as or different from at least one of the first adhesive layer 40 , the second adhesive layer 50 , and the third adhesive layer 80 . Since it is the same as what was described in the 1st adhesive bond layer part of 1st Embodiment, description about this 4th adhesive bond layer is abbreviate|omitted.

The above-described flexible printed circuit boards 100A and 100B of the present invention may be manufactured according to a conventional method known in the art, for example, a roll-to-roll process. For example, a first insulating film having a plurality of circuit wirings formed on one surface and a second insulation film having an adhesive layer formed on one surface are disposed to face each other, and then integrated by pressing and heating by a roll-to-roll continuous automatic method.

Specifically, the flexible printed circuit board (100A, 100B) of the present invention (S100) while transferring the first laminate in which a metal foil is disposed on one surface of the first insulating film in one direction (eg, MD), forming a plurality of circuit wirings by patterning the metal foil; (S200) forming a terminal exposed portion and an alignment portion by punching a portion of the second laminate while transferring a second laminate having a first adhesive layer disposed on one surface of the second insulating film in one direction; (S300) The first laminate transferred in step (S100) and the second laminate transferred in step (S200) may be manufactured by a method comprising laminating them while moving in one direction. Optionally, a second adhesive layer may be interposed between the first insulating film and the metal foil. However, it is not limited only by the manufacturing method, and the steps of each process may be modified or selectively mixed as needed. In particular, there is no temporal precedence between the steps (S100) and (S200).

Step (S100): while supplying and moving the first laminate in which a metal foil is disposed on one surface of the first insulating film in one direction, the metal foil is patterned to form a plurality of circuit wirings .

The first laminate includes a first insulating film and a metal foil disposed on the first insulating film, and optionally a second adhesive layer interposed between the first insulating film and the metal foil, in one direction ( eg, in the form of a roll continuous in the longitudinal direction, MD).

The first insulating film is a polymer film used as the first insulating layer 10 described in the first embodiment, and a detailed description thereof is omitted because it is the same as that described in the first insulating layer 10 .

The metal foil may be directly formed on the first insulating film, or formed separately, then applied on the first insulating film and then adhered to the first insulating film through a dried second adhesive layer.

The material of the metal foil is omitted because it is the same as described for the first circuit wiring. In addition, since it is the same as that of 2nd Embodiment, description of a 2nd adhesive bond layer is also abbreviate|omitted.

The method for applying the second adhesive layer is not particularly limited as long as it is commonly known in the art, and for example, a dip coat method, an air knife coat method, a curtain coat method, a wire bar coat method, a gravure coat method, a comma coat method, a slot coat method method, an extrusion coating method, a spin coating method, a slit scan method, an inkjet method, and the like. The drying process may be appropriately carried out within conventional conditions known in the art, for example, may be carried out at a temperature of about 100 to 200 ℃.

The patterning method of the metal foil is not particularly limited as long as it is a circuit patterning process known in the art. For example, there is a printing method, a photoresist method, a wet or dry etching method, etc., but is not limited thereto.

Step (S200): While transferring the second laminate on which the adhesive layer is disposed on one surface of the second insulating film in one direction, a part of the second laminate is punched to form terminal exposed parts and alignment parts .

The second laminate includes a second insulating film and a first adhesive layer disposed on the second insulating film, and is in the form of a roll continuous in one direction (eg, MD).

The second insulating film is a portion that becomes the second insulating layer 30 of the final flexible printed circuit boards 100A and 100B, and a description thereof is omitted because it is the same as described in the first embodiment. In addition, since it is the same as that of 1st Embodiment, description about a 1st adhesive bond layer is abbreviate|omitted.

The device for punching the second laminate may be a punching unit generally known in the art, for example, a laser device, a punching machine (mold punching, rotary punching), or the like. The terminal exposed portion and the alignment portion are formed by vertically penetrating the second laminate by using such a punching unit. Here, the terminal exposed portion is a portion in which the terminal portion of the circuit wiring is exposed, and may be formed in a portion where the terminal portion of the circuit wiring is located, for example, an edge and/or a center portion of the second laminate. On the other hand, the alignment part is aligned with the alignment pin, the alignment mark, or the alignment hole provided in the first insulating film on a plane.

Step (S300): The first laminate transferred in step (S100) and the second laminate transferred in step (S200) are laminated by thermocompression bonding while moving in one direction .

Step (S300) aligns the positions of the second laminate transferred in step (S200) on the first laminate transferred in step (S100), and then thermocompresses them by a pair of heating rollers. Optionally, the first laminate and the second laminate may be temporarily bonded after alignment. At this time, the plurality of circuit wirings of the first laminate and the first adhesive layer of the second laminate are laminated to face each other, and the first insulating film and the second insulating film are attached to each other by the first adhesive layer.

The alignment between the first laminate and the second laminate is not particularly limited as long as it is an alignment process generally known in the art. For example, the center of the alignment part of the second laminate is the center of the alignment mark of the first laminate and the make it match

The temporary bonding conditions of the first laminate and the second laminate may be appropriately adjusted within a conventional range known in the art. For example, it may be carried out at a compression speed of about 0.1-5 m/min with a linear pressure of about 0.1-1 ton/m using a pair of heating rollers having a roller temperature of about 50-150° C., but is not particularly limited thereto .

The thermocompression bonding conditions may be appropriately adjusted within a conventional range known in the art. For example, it can be carried out at a compression speed of about 0.1-5 m/min with a linear pressure of about 0.5-4 ton/m using a pair of heating rollers having a roller temperature of about 50-300° C., but is not particularly limited thereto. .

According to the method described above, in the present invention, a plurality of circuit wirings 20, a first adhesive layer 40, and a second insulating layer 30 are sequentially disposed on the first insulating layer 10, the first insulating layer The flexible printed circuit boards 100A and 100B extending in one direction along the bonding surface of the layer and the second insulating layer and having a thickness deviation in the range of about 1 to 5 μm may be manufactured. In addition, during the thermocompression bonding, the first terminal part 21 of the circuit wiring in the first laminate is exposed to the outside through the terminal exposed part of the second laminate, so that the first terminal part 21 of the circuit wiring has an open surface . At this time, the first adhesive layer in the second laminate is melted by a pair of heating rollers, and a part of the melted adhesive of the first adhesive layer flows onto the open surface by the pressure of the heating roller and then hardens, so that the open surface An adhesive bead layer 41 having directionality in the machine direction may be formed on one side of the .

The above-described flexible printed circuit boards 100C and 100D of the present invention may be manufactured according to a conventional method known in the art, for example, a roll-to-roll process. For example, after arranging second insulating films each having an adhesive layer formed on one side above and below the first insulating film having a plurality of circuit wirings formed on both sides, pressurizing and heating by a roll-to-roll continuous automatic method to integrate them. can

Specifically, the flexible printed circuit board (100C, 100D) of the present invention (S10) a first laminate in which first and second metal foils are respectively disposed on both sides of the first insulating film in one direction (eg, forming a plurality of first and second circuit wirings by patterning the first and second metal foils while transferring them to MD); (S20) forming a terminal exposed portion and an alignment portion by punching a portion of the second laminate while transferring the second laminate having the first adhesive layer disposed on one surface of the second insulating film in one direction; (S30) forming a terminal exposed part and an alignment part by punching a part of the third laminate while transferring a third laminate having a third adhesive layer disposed on one surface of the third insulating film in one direction; (S40) The first laminate transferred in the step (S10), the second laminate transferred in the step (S20), and the third laminate transferred in the step (S30) are laminated while moving in one direction It may be prepared by a method comprising the steps. Optionally, a second adhesive layer may be interposed between the first insulating film and the first metal foil, and/or a fourth adhesive layer may be interposed between the first insulating film and the second metal foil. However, it is not limited only by the manufacturing method, and the steps of each process may be modified or selectively mixed as needed. In particular, there is no temporal precedence between the steps (S10), (S20) and (S30).

Step (S10): while supplying and moving a first laminate in which first and second metal foils are respectively disposed on both sides of the first insulating film in one direction, patterning the first and second metal foils to form a plurality of first and second circuit wirings .

Step (S10) is performed in the same manner as described in step (S100) of the above-described manufacturing method, except for using the first laminate in which the first and second metal foils are respectively disposed on both surfaces of the first insulating film.

The first metal foil and the second metal foil may be the same as or different from each other. At this time, the first metal foil is patterned to form a plurality of first circuit wirings 20 , and the second metal foil is patterned to form a plurality of second circuit wirings 60 . However, the patterning process of the first metal foil and the patterning process of the second metal foil may be performed simultaneously, or the patterning process of the second metal foil may be performed after the patterning process of the first metal foil.

In addition, the first laminate includes a second adhesive layer 50 interposed between the first insulating film and the first metal foil, and/or a fourth adhesive layer 90 interposed between the first insulating film and the second metal foil. may include more.

The description of the second adhesive layer is the same as that described in the second embodiment, and the description of the fourth adhesive layer is the same as that described in the fourth embodiment.

Step (S20): A portion of the second laminate is punched out while transferring the second laminate in which the first adhesive layer is disposed on one surface of the second insulating film in one direction to form an exposed terminal part and an alignment part.

The description of the step (S20) is omitted because it is the same as described in the step (S200) of the above-described manufacturing method.

Step (S30): A portion of the third laminate is punched out while transferring the third laminate on which the third adhesive layer is disposed on one surface of the third insulating film in one direction to form an exposed terminal part and an alignment part.

Step (S30) is performed in the same manner as in step (S20), except that the third laminate is used instead of the second laminate in step (S20).

In this case, the third laminate includes a third insulating film and a third adhesive layer disposed on the third insulating film, and is in the form of a roll continuous in one direction (eg, longitudinal direction, MD).

The third insulating film is a part that becomes the third insulating layer 70 of the final flexible printed circuit boards 100C and 100D, and a description thereof is omitted because it is the same as described in the third embodiment.

In addition, since the description of the 3rd adhesive bond layer is the same as that of 3rd Embodiment, it is abbreviate|omitted.

Step (S40): While moving the first laminate transferred in step (S10), the second laminate transferred in step (S20), and the third laminate transferred in step (S30) in one direction, these combine

In step (S40), the positions of the second stack transported in step (S20) and the third stack transported in step (S30) are located above and below the first stacked body transported in step (S10). After alignment, they are thermocompression-bonded by a pair of heating rollers. Optionally, the second laminate-first laminate-third laminate may be temporarily bonded after alignment. At this time, while laminating the plurality of first circuit wirings of the first laminate and the first adhesive layer of the second laminate to face each other, the plurality of second circuit wirings of the first laminate and the third adhesive of the third laminate Lay the layers facing each other. However, after laminating the second laminate on one surface of the first laminate by a pair of heating rollers, the third laminate may be laminated on the other surface of the first laminate by a pair of heating rollers.

This step (S40) is performed except that the first laminate transferred in step (S10), the second laminate transferred in step (S20), and the third laminate transferred in step (S30) are used. , is performed in the same manner as in step (S300) described above. Accordingly, since the alignment method, temporary bonding condition, and thermocompression bonding condition between the laminates are the same as those described in the above-described step (S300), they are omitted.

By the above-described method, the present invention provides a plurality of first circuit wirings 20, a first adhesive layer 40, and a second insulating layer 30 sequentially disposed on one surface of the first insulating layer 10. , a plurality of second circuit wirings 60 , a third adhesive layer 80 and a third insulating layer 70 are sequentially disposed on the other surface of the first insulating layer 10 , the first insulating layer and the second It is possible to manufacture the flexible printed circuit boards 100C and 100D extending in one direction along the bonding surface of the insulating layer and having a thickness deviation of about 1 to 5 μm. In addition, the flexible printed circuit board (100C, 100D) of the present invention includes a second adhesive layer 50 interposed between the first insulating layer 10 and the plurality of first circuit wires 20; and/or may further include a fourth adhesive layer 90 interposed between the first insulating layer 10 and the plurality of second circuit wires 60 . In addition, during the thermocompression bonding, each terminal portion of the first and second circuit wirings 20 and 60 in the first laminate is exposed to the outside through the terminal exposed portions of the second laminate and the third laminate, so that each terminal portion It has an open surface, and an adhesive bead layer 41 having directionality in the machine direction may be formed on one side of the open surface.

Hereinafter, a battery cell module connection member according to the present invention will be described with reference to FIGS. 9 to 10 .

The battery cell module connecting member according to the present invention includes the above-described flexible printed circuit boards 100A, 100B, 100C, and 100D, for example, a bus bar module that electrically connects terminals of battery cells adjacent to each other in the battery cell module. can be In addition, the battery cell module connecting member electrically connects the battery cell module to the external board through the first connector part 23 and/or the second connector part (not shown) of the flexible printed circuit board.

According to one example, the battery cell module connecting member is shown in FIG. 9, the flexible printed circuit board 100; and located on the same plane as the contact surface between the circuit wiring 20 and the second insulating layer 30 (or the first adhesive layer 40) of the flexible printed circuit board 100, and each in the flexible printed circuit board It may include a bus bar (hereinafter, 'first bus bar') 200 electrically connected to the terminal part (hereinafter, 'first terminal part') of the circuit wiring. At this time, when the flexible printed circuit board 100 has a double-sided structure like the flexible printed circuit boards 100C and 100D of the third and fourth embodiments, the battery cell module connecting member is the second circuit wiring 20 and the third The second bus bar ( not shown) may be further included.

The flexible printed circuit board 100 is a band-shaped member extending along the bus bar arrangement direction, and a description thereof is provided in the flexible printed circuit boards 100A, 100B, 100C, 100D of the first to fourth embodiments. It is omitted because it is the same as described.

The first and second bus bars are metal members electrically connected to the terminal part of the battery cell, and as shown in FIG. 9 , each bus bar is spaced apart from each other along both edges of the flexible printed circuit board 100 . has been

As shown in FIG. 10 , the first bus bar 200 is positioned on the same plane as the contact surface between the first circuit wiring 20 and the second insulating layer 30 (or the first adhesive layer 40 ). However, it is electrically connected to the first terminal part 21 of each circuit wiring 20 . At this time, the first bus bar 200 is in direct surface contact with the first terminal part 21 . Also, although not shown, the second bus bar (not shown) is positioned on the same plane as the contact surface between the second circuit wiring 60 and the third insulating layer 70 (or the third adhesive layer 80 ). However, it is electrically connected to the second terminal portion of each circuit wiring 60 . At this time, the second bus bar is in direct surface contact with the second terminal part. Accordingly, the first and second bus bars and the first and second terminal portions of the present invention are tightly coupled to each other, thereby improving the performance of the battery cell module and ensuring stability.

The number of the first and second bus bars can be adjusted according to the length of the flexible printed circuit board 100 and the size of the bus bars, respectively, for example, the length of the flexible printed circuit board 100 along one edge of the flexible printed circuit board. It may be 5-20 pieces per 500 mm. For example, when the length of the flexible printed circuit board 100 is 500 to 1,000 mm, the number of bus bars may be 5 to 40.

Hereinafter, the present invention will be described in more detail by way of Examples and Comparative Examples. However, the present invention is not limited thereto.

<Example 1>

1-1. Manufacturing of flexible printed circuit boards

A flexible printed circuit board was continuously manufactured using a roll-to-roll apparatus as follows.

First, while continuously supplying the first laminate from the first laminate supply roller, the copper foil of the first laminate was exposed in a desired pattern and then etched to form a plurality of circuit wirings. At this time, the first laminate had a structure in which a copper foil (thickness: 35 μm) was disposed on one surface of the PI film (thickness: 25 μm), and was in the form of a roll continuous in the traveling direction. On the other hand, while continuously supplying the second laminate from the second laminate supply roller, a part of the supplied second laminate was punched out with an excimer laser machine to form terminal exposed parts and alignment parts. At this time, the second laminate is a coverlay film (DPF-200 of Doosan Corporation), and has a structure in which an adhesive layer (thickness: 30 µm) is laminated on a second insulating film (thickness: 25 µm), and the machine transport direction (MD) was in the form of a continuous roll. Thereafter, while the terminal exposed portion and the alignment portion are formed and the continuously supplied second laminate is moved in one direction, a plurality of circuit wirings are formed and stacked on top of the continuously supplied first laminate. , using a vision unit to align the alignment marks of the first laminate with the centers of the alignment portions of the second laminate, and then a pair of heating rollers (roller temperature: 100 ° C, linear pressure: 1 ton/m, Pressing speed: 1 m/min) at 100 °C, followed by bonding (thermocompression bonding) with a pair of heating rollers (roller temperature: 200 °C, linear pressure: 3 ton/m, pressing speed: 1 m/min) Then, it was cut into predetermined sizes (MD length: 500 mm, TD length: 500 mm) to prepare a final flexible printed circuit board.

As shown in FIG. 11 , in the flexible printed circuit board manufactured above, an adhesive bead layer was formed on one side of the open surface of the terminal part of the circuit wiring. At this time, it was confirmed that the adhesive bead layer had directionality in the roll direction (MD).

1-2. Manufacturing of busbar modules

A bus bar module was manufactured by directly contacting the bus bar to each terminal of the flexible printed circuit board manufactured in Example 1-1. At this time, the total number of bus bars was 26.

<Comparative Example 1>

1-1. Manufacturing of flexible printed circuit boards

A flexible printed circuit board was manufactured using a hot press device as follows.

First, while continuously supplying the first laminate from the first laminate supply roller, the copper foil of the first laminate was exposed in a desired pattern and then etched to form a plurality of circuit wirings. At this time, the first laminate had a structure in which a copper foil (thickness: 35 μm) was disposed on one surface of a PI film (thickness: 25 μm), and was in the form of a continuous roll in the traveling direction. Thereafter, the first laminate on which the plurality of circuit wirings were formed was cut into predetermined sizes (MD length: 500 mm, TD length: 500 mm). On the other hand, while continuously supplying the second laminate from the second laminate supply roller, a part of the supplied second laminate is punched out according to the circuit wiring design of the first laminate with an excimer laser machine to expose the terminals A portion and an alignment portion were formed. At this time, the second laminate is a coverlay film (DC-200 from Doosan Corporation), and has a structure in which an adhesive layer (thickness: 30 µm) is laminated on a second insulating film (thickness: 25 µm), and the machine transport direction (MD) was a continuous roll form. Thereafter, the second laminate on which the terminal exposed part and the alignment part were formed was cut to a predetermined size (MD length: 500 mm, TD length: 500 mm). Next, the cut second laminate was disposed on the circuit wiring of the cut first laminate. When disposing the cut second laminate, the center of the alignment mark of the first laminate and the center of the alignment portion of the second laminate was matched using a vision unit. Thereafter, a flexible printed circuit board (MD length: 500 mm, TD length: 500 mm) was prepared by thermocompression bonding with a hot press machine (temperature: 150° C., surface pressure: 80 kgf, compression time: 1 hr). In this case, the terminal portion of each circuit wiring is exposed through the terminal exposed portion of the second laminate to have an open surface, and an adhesive bead is formed on one side of the open surface.

As shown in FIG. 12 , in the flexible printed circuit board manufactured above, an adhesive bead layer was formed on one side of the open surface of the terminal part of the circuit wiring. At this time, it was confirmed that the adhesive bead layer had almost constant length in the roll direction (MD), and thus had no directionality.

1-2. Manufacturing of busbar modules

A bus bar module was manufactured by directly contacting the bus bar to each terminal of the flexible printed circuit board manufactured in Comparative Example 1-1. At this time, the total number of busbars was 26.

<Experimental Example 1> - Thickness uniformity of flexible printed circuit board

The thickness uniformity of the flexible printed circuit board according to the present invention was measured as follows, and the results are shown in Tables 1-2 and FIG. 13 .

(1) Measurement of thickness deviation of flexible printed circuit boards

The flexible printed circuit boards prepared in Example 1 and Comparative Example 1 were partitioned at intervals of 25 mm in width and 25 mm in length, and then the thickness of 100 places was measured with a thickness gauge (micrometer), and the measurement results are shown in Table 1 and Table 2.

(2) Cross-sectional image analysis of flexible printed circuit boards

Each of the flexible printed circuit boards prepared in Example 1 and Comparative Example 1 was partitioned at intervals of 25 mm in width and 25 mm in length, and then the cross section at 225 mm in MD and TD was analyzed using a microscope, and the The results are shown in FIG. 13 .

Example 1 MD side thickness measurement position (mm) 25 75 125 175 225 275 325 375 425 475 TD side thickness measurement location
(mm) 25 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 75 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 125 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 175 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 225 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 275 0.111 0.111 0.111 0.111 0.111 0.112 0.112 0.111 0.111 0.111 325 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 375 0.110 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 425 0.111 0.111 0.111 0.111 0.112 0.112 0.112 0.111 0.111 0.111 475 0.111 0.111 0.111 0.111 0.112 0.112 0.111 0.111 0.111 0.111

Comparative Example 1 MD side thickness measurement position (mm) 25 75 125 175 225 275 325 375 425 475 TD side thickness measurement location
(mm) 25 0.101 0.102 0.103 0.104 0.106 0.107 0.106 0.104 0.102 0.101 75 0.103 0.104 0.104 0.106 0.107 0.107 0.107 0.106 0.104 0.102 125 0.104 0.106 0.106 0.108 0.108 0.109 0.108 0.107 0.107 0.103 175 0.106 0.107 0.109 0.110 0.110 0.111 0.111 0.109 0.108 0.105 225 0.107 0.109 0.110 0.111 0.113 0.113 0.112 0.111 0.109 0.107 275 0.105 0.108 0.108 0.110 0.111 0.112 0.111 0.109 0.108 0.106 325 0.104 0.106 0.107 0.108 0.110 0.111 0.109 0.108 0.106 0.104 375 0.103 0.105 0.106 0.107 0.109 0.109 0.107 0.106 0.105 0.102 425 0.102 0.104 0.105 0.106 0.108 0.108 0.106 0.104 0.103 0.101 475 0.102 0.103 0.104 0.106 0.107 0.106 0.104 0.103 0.102 0.100

As shown in Table 1, Example 1 had an average thickness of about 0.111 mm and a thickness variation of about 1 μm. On the other hand, Comparative Example 1 had an average thickness of 0.106 mm, and a thickness deviation of about 12 µm (see Table 2). Here, the thickness deviation was the difference between the highest thickness and the lowest thickness.

On the other hand, as shown in FIG. 13(a), the flexible printed circuit board of Example 1 had an overall uniform thickness. On the other hand, in Comparative Example 1, the thickness of the other parts was thinner than that of the central part, and thus the overall thickness was non-uniform (see FIG. 13(b) ).

As described above, it was confirmed that the thickness of the flexible printed circuit board of the present invention was uniform as a whole.

10: first insulating layer, 20: circuit wiring, first circuit wiring;
21: terminal part, 22: internal circuit part,
23: connector portion, 30: second insulating layer,
40: a first adhesive layer, 50: a second adhesive layer,
60: a second circuit wiring, 70: a third insulating layer;
80: a third adhesive layer, 90: a fourth adhesive layer;
100, 100A, 100B, 100C, 100D: flexible printed circuit board,
200: a bus bar, a first bus bar;
1000: no battery cell module connection

Claims (14)

a first insulating layer;
a plurality of circuit wirings disposed on one surface of the first insulating layer and having a terminal portion electrically connected to a bus-bar at one end;
a second insulating layer covering the plurality of circuit wirings and continuously formed along a longitudinal direction of the first insulating layer; and
A first adhesive layer interposed between the first insulating layer and the second insulating layer
As a flexible printed circuit board comprising a,
The flexible printed circuit board is formed to extend in one direction along the bonding surface of the first insulating layer and the second insulating layer, and the thickness deviation is in the range of 1 to 5 μm. According to claim 1,
The total thickness deviation of the second insulating layer and the first adhesive layer is in the range of 1 to 5 μm, the flexible printed circuit board. According to claim 1,
The terminal part includes an open surface with an exposed surface,
An adhesive bead layer having a directionality in the machine direction of the flexible printed circuit board is formed on one side of the open surface. According to claim 1,
The terminal portion will be in direct surface contact with the bus bar, a flexible printed circuit board. According to claim 1,
The circuit wiring is located at the other end and further includes a connector part electrically connected to an external circuit board. According to claim 1,
The second insulating layer has a ratio (L _MD /L _TD ) of a length (L _MD ) to a length (L _TD ) in the width direction in a range of 1 to 150, a flexible printed circuit board. 7. The method of claim 6,
The length of the second insulating layer in the longitudinal direction (L _MD ) is in the range of 500 to 3,000 mm, and the length in the width direction (L _TD ) is in the range of 20 to 500 mm, the flexible printed circuit board. According to claim 1,
The flexible printed circuit board further comprising a second adhesive layer interposed between the first insulating layer and the plurality of circuit wires. According to claim 1,
a plurality of second circuit wirings disposed on the other surface of the first insulating layer and having a second terminal portion electrically connected to the bus bar at one end;
a third insulating layer covering the plurality of second circuit wirings and continuously formed along a longitudinal direction of the first insulating layer; and
A third adhesive layer interposed between the first insulating layer and the third insulating layer
Which will further include, a flexible printed circuit board. 10. The method of claim 9,
The deviation of the total thickness of the third insulating layer and the third adhesive layer is in the range of 1 to 5 μm, the flexible printed circuit board. 10. The method of claim 9,
a second adhesive layer interposed between the first insulating layer and the plurality of first circuit wirings; and at least one of a fourth adhesive layer interposed between the first insulating layer and the plurality of second circuit wires. A battery cell module connecting member comprising the flexible printed circuit board according to any one of claims 1 to 11. 13. The method of claim 12,
The battery cell module connecting member further comprising a bus bar positioned on the same plane as a contact surface between the second insulating layer and the first circuit wiring and electrically connected to each terminal of the flexible printed circuit board. 14. The method of claim 13,
The battery cell module connecting member further comprising a second bus bar positioned on the same plane as a contact surface between the third insulating layer and the second circuit wiring and electrically connected to each second terminal portion of the flexible printed circuit board.

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