WO2019240356A1

WO2019240356A1 - Battery pack

Info

Publication number: WO2019240356A1
Application number: PCT/KR2019/003113
Authority: WO
Inventors: 최재혁
Original assignee: 삼성에스디아이(주)
Priority date: 2018-06-12
Filing date: 2019-03-18
Publication date: 2019-12-19
Also published as: CN111295777A; KR102519555B1; CN111295777B; KR20190140581A

Abstract

An embodiment of the present invention relates to a battery pack. The technical problem to be solved is to provide a battery pack configured to safely insulate a connection area (e.g., a solder) of a flexible circuit board connected to a protection circuit module (e.g., a hard circuit board) from the outside environment without coating the connection area with an ultraviolet curable resin, to provide a case holder that can be applied to automation equipment, and to suppress cracking in the connection area by preventing stress from being applied to the connection area when the flexible circuit board is bent. To this end, disclosed is a battery pack comprising: a battery cell having a cell tab; a protective circuit module electrically connected to the cell tab; the flexible circuit board electrically connected to the protective circuit module through the connection area; and the case holder configured to cover the protective circuit module and the connection area, wherein the case holder has a thickness of an area corresponding to the connection area being thinner than a thickness of an area corresponding to an outer side of the connection area.

Description

Battery pack

An embodiment of the present invention relates to a battery pack.

A secondary battery is a battery that can be charged and discharged unlike a primary battery that is not rechargeable. Low-capacity secondary batteries are used in portable electronic devices such as smartphones, feature phones, notebook computers, digital cameras, and camcorders. Large-capacity secondary batteries are used to power motors and power storage batteries for hybrid vehicles and electric vehicles. Widely used.

The secondary battery may include an electrode assembly consisting of a positive electrode and a negative electrode, an exterior material containing the same, an electrode terminal connected to the electrode assembly, and the like. Exterior materials can be classified into round, square and pouch types according to their shape. Among these, the pouch type secondary battery may be formed of a pouch or a laminate packaging material which is easily deformed in various shapes and has a small weight.

The above-described information disclosed in the background technology of the present invention is only for improving the understanding of the background of the present invention, and thus may include information that does not constitute the prior art.

An embodiment of the present invention safely insulates a connection area (eg soldering) of a flexible circuit board connected on a protective circuit module (eg, a hard circuit board) from the external environment without coating with an ultraviolet curable resin, Provided is a case holder that can be applied to an automated facility, and provides a battery pack that can suppress the occurrence of cracks in the connection area by applying a stress to the connection area when bending the flexible circuit board.

A battery pack according to an embodiment of the present invention includes a battery cell having a cell tab; A protection circuit module electrically connected to the cell tab; A flexible circuit board electrically connected to the protection circuit module through a connection area; And a case holder covering the protection circuit module and the connection area, wherein the case holder may have a thickness of an area corresponding to the connection area being thinner than a thickness of an area corresponding to an outer side of the connection area.

In this way, the case holder covers the connection area to insulate the connection area from the outside, increases the rigidity of the case holder so as not to be damaged in the automation facility, and instead of applying stress to the connection area when bending the flexible circuit board. It is applied to the bent area so that the connection area is not cracked.

The case holder may include a first region corresponding to one surface of the protection circuit module and having a first thickness; A second region corresponding to the connection region and having a second thickness smaller than the first thickness; And a third region corresponding to the other surface of the protection circuit module and having a third thickness between the first thickness and the second thickness.

In this way, the second region of the case holder having a second thickness smaller than the first thickness prevents the connection region formed in the protruding shape from interfering with the second region and is easily coupled in the case holder. In addition, the protection circuit module is securely protected from the external environment by the first region of the case holder having the thickest first thickness. Further, the thickness of the battery pack is made thinner by the third region of the case holder having the thinnest third thickness.

Each of the first and second regions may include a flat upper surface and a flat lower surface as an opposite surface of the upper surface, respectively, and the upper surfaces of the first and second regions may form the same plane with each other. The lower surface can be different from each other.

In this way, the lower surfaces of the first and second regions are different from each other. For example, the lower surface of the second region is relatively positioned at an upper portion, whereby a connection region formed in a protruding shape is formed in the second region of the case holder. It can be easily combined.

The connection area may comprise soldering.

In this way, the flexible circuit board is electrically, mechanically and stably connected to the protective circuit module by soldering.

An edge of the second region may be formed outside the edge of the connection region.

In this way, the edge of the second region of the case holder is formed outside the edge of the connection region so that the flexible circuit board is in contact with the edge of the second region when the flexible circuit board is bent, whereby stress is applied to the connection region. Instead of being applied, it is applied to an area of the flexible circuit board outside of it, and eventually cracks in the connection area are prevented.

The first region of the case holder may include a first escape portion formed in an area corresponding to the test pad formed in the protection circuit module.

In this manner, the first evacuation portion is formed in an area corresponding to the test pad of the protection circuit module, so that the test probe can be easily accessed at the end of the battery pack manufacturing process.

The third region of the case holder may include a third hide formed in an area corresponding to the cell tab.

In this way, the tab bending of the protective circuit module is facilitated by the third cover of the case holder, and the cell tab is easily welded to the tab of the protective circuit module by welding equipment.

The second region may include a protrusion that protrudes outward from the first region.

In this way, the second region of the case holder includes the protrusion, so that when the flexible circuit board is bent, the flexible circuit board is brought into close contact with the protrusion, whereby bending stress is not applied to the connection area but instead of one of the flexible circuit boards outside thereof. Applied to the area, and eventually cracking of the connection area is prevented.

The cell tab of the battery cell is bent so that the third region of the case holder may be adhered to the terrace of the battery cell through an adhesive tape.

In this way, the case holder is adhered onto the terrace, whereby an increase in the thickness of the battery pack can be prevented.

As an example, the embodiment of the present invention allows the connection area formed for the connection of the flexible circuit board to the protection circuit module to be covered by the case holder, so that the connection area is safely insulated / protected from the external environment.

As another example, the embodiment of the present invention is formed by making the thickness of a predetermined area of the case holder covering the connection area thinner than the thickness of the other peripheral area (especially, by making the thickness of the lower area facing the connection area thinner). This allows the connection area to be easily coupled to the case holder without interfering with the case holder. Moreover, the upper surface of the case holder corresponding to the connection area is not convexly deformed to have a substantially flat state, so that a poor appearance of the battery pack can be prevented.

In addition, since the embodiment of the present invention does not have to form a wide escape portion as in the prior art in an area corresponding to the connection area, the rigidity of the case holder is not lowered, thereby damaging the case holder when handling the case holder in an automation facility. Do not

As another example, the embodiment of the present invention allows the flexible circuit board to be folded when the flexible circuit board is bent upward by making the edge of the case holder more outward than the edge of the connection area, or by forming a protrusion in the case holder. The edges or protrusions are first brought into contact with each other, so that stress is applied to the contact portion and stress is not applied to the connection area, thereby preventing cracking of the connection area.

1A, 1B and 1C are perspective, cross-sectional and exploded perspective views of a battery pack according to an embodiment of the present invention.

2A, 2B and 2C are front perspective view, front view and rear bottom perspective view showing a case holder used in a battery pack according to an embodiment of the present invention.

3A and 3B are perspective and cross-sectional views illustrating a relationship between a protection circuit module, a flexible circuit board, and a case holder in a battery pack according to an embodiment of the present invention, and FIG. 3C illustrates a bent state of the flexible circuit board. Perspective view.

4A, 4B, and 4C are plan views, front views, and bottom views illustrating a relationship between a protection circuit module, a flexible circuit board, and a case holder in a battery pack according to an embodiment of the present invention.

5A and 5B are perspective views and cross-sectional views illustrating a relationship between a protection circuit module, a flexible circuit board, and a case holder in a battery pack according to another exemplary embodiment of the present invention, and FIG. 5C illustrates a bent state of the flexible circuit board. Perspective view.

6A, 6B, and 6C are plan views, front views, and bottom views illustrating a relationship between a protection circuit module, a flexible circuit board, and a case holder in a battery pack according to another embodiment of the present invention.

7A and 7B illustrate an electrical connection state between a protection circuit module and a battery cell in a method of manufacturing a battery pack according to an embodiment of the present invention.

8A and 8B illustrate tab bending states of a protection circuit module in a method of manufacturing a battery pack according to an embodiment of the present invention.

9A and 9B illustrate a bent state of a cell tab in a method of manufacturing a battery pack according to an embodiment of the present invention.

10A and 10B are diagrams illustrating a tape attachment state in a method of manufacturing a battery pack according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art, and the following examples can be modified in various other forms, and the scope of the present invention is It is not limited to an Example. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the inventive concept to those skilled in the art.

In addition, in the following drawings, the thickness or size of each layer is exaggerated for convenience and clarity of description, the same reference numerals in the drawings refer to the same elements. As used herein, the term "and / or" may include any and all combinations of one or more of the listed items. In addition, the term "connected" in this specification means not only the case where the A member and the B member are directly connected, but also the case where the A member and the B member are indirectly connected by interposing the C member between the A member and the B member. do.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. Also, as used herein, “comprise, include” and / or “comprising, including” refer to shapes, numbers, steps, operations, members, elements, and / or these mentioned. It is intended to specify the presence of a group and not to exclude the presence or addition of one or more other shapes, numbers, operations, members, elements and / or groups.

Although the terms first, second, etc. are used herein to describe various members, parts, regions, layers, and / or parts, these members, parts, regions, layers, and / or parts are defined by these terms. It is obvious that not. These terms are only used to distinguish one member, part, region, layer or portion from another region, layer or portion. Accordingly, the first member, part, region, layer or portion, which will be described below, may refer to the second member, component, region, layer or portion without departing from the teachings of the present invention.

Terms relating to spaces such as "beneath", "below", "lower", "above", and "upper" are associated with one element or feature shown in the figures. It can be used for easy understanding of other elements or features. Terms related to this space are for easy understanding of the present invention according to various process conditions or use conditions of the present invention, and are not intended to limit the present invention. For example, if an element or feature in the figures is inverted, the element or feature described as "bottom" or "bottom" will be "top" or "top". Thus, "bottom" is a concept encompassing "top" or "bottom".

1A, 1B and 1C are perspective, cross-sectional and exploded perspective views of a battery pack 100 according to an embodiment of the present invention.

As shown in Figure 1a, 1b and 1c, the battery pack 100 according to an embodiment of the present invention is a battery cell 110, a protective circuit module 120, a flexible circuit board 130 and a case holder 140 may be included.

In addition, the battery pack 100 according to an embodiment of the present invention is an insulating tape 150, the protection circuit module 120 and the case holder 140 interposed between the battery cell 110 and the case holder 140. It may further include a covering protective tape 160, a cover tape 170 covering three lateral sides of the battery cell 110, and / or a top tape 180 covering an upper side of the battery cell 110.

The battery cell 110 extends outwardly through an electrode assembly (not shown) including a positive electrode plate, a separator and a negative electrode plate, a pouch sheathing material 111 surrounding the electrode assembly, etc., and penetrating the pouch sheathing material 111 from the electrode assembly. It may include a positive cell tab 112a and a negative cell tab 112b.

Here, the positive cell tab 112a and the negative cell tab 112b may be collectively referred to as the cell tab 112. In addition, the cell tab 112 may be extended and bent a predetermined length forward through the relatively thin terrace 113 provided on the front surface of the pouch packaging material 111.

The protection circuit module 120 may include a hard circuit board 121 electrically connected to the cell tab 112 provided in the battery cell 110. In addition, the anode cell tab 112a of the battery cell 110 is electrically connected to the PCM cathode conductive tab 122a provided on the rigid circuit board 121, and the cathode cell tab 112b of the battery cell 110 is a rigid circuit. It may be electrically connected to the PCM negative electrode conductive tab 122b provided on the substrate 121.

Here, the PCM cathode conductive tab 122a and the PCM cathode conductive tab 122b may be collectively referred to as a conductive tab 122. The protection circuit module 120 serves to prevent overcharge, overdischarge, and / or overcurrent of the battery cell 110. Of course, for the protection operation, a plurality of electronic components 123 may be mounted on the rigid circuit board 121.

The flexible circuit board 130 may be connected to the protection circuit module 120 through the connection area 131. For example, the flexible circuit board 130 may be electrically connected through a connection area 131 such as solder or solder, which protrudes from the rigid circuit board 121. Here, the flexible circuit board 130 may be designed in various forms, and may further include a connector 132 for connecting to an external device at the end.

The flexible printed circuit board 130 may be referred to as a separated flexible printed circuit board 130. The detachable flexible circuit board 130 has a higher degree of design freedom compared to an integrated circuit board having a limited design. In addition, the separated flexible printed circuit board 130 may improve the efficiency of the allowable current by designing a resistance value lower than that of the integrated circuit board. In addition, the separate flexible printed circuit board 130 is easy to apply design standardization. For example, the hard circuit board 121 of the protection circuit module 120 is to be used in common, the flexible circuit board 130 can be used in various ways by changing the design. In addition, the detachable flexible circuit board 130 may reduce substrate scrap compared to an integrated circuit board. In one example, the production arrangement of the separated flexible printed circuit board 130 may be efficiently arranged to improve production yield.

The case holder 140 is coupled to the protection circuit module 120 to protect and insulate the protection circuit module 120 from the external environment. In particular, the case holder 140 covers not only the protection circuit module 120 but also the connection area 131 of the flexible circuit board 130 formed in the protection circuit module 120, thereby protecting and insulating it from the external environment. . The case holder 140 may be formed by a thin film injection process using an insulating resin, and the thickness of the case holder 140 does not increase the thickness of the battery pack 100. The case holder 140 is formed in a generally “⊃” shape and is coupled to the protection circuit module 120, and the upper, lower, rear and both sides of the protection circuit module 120, except the front of the protection circuit module 120. It forms a covering. Of course, the front of the protective circuit module 120 and the case holder 140 may be covered with a protective tape 160.

The insulating tape 150 may be interposed between the terrace 113 of the battery cell 110 and the case holder 140 in a substantially “┛” shape, which may stably secure the case holder 140 on the terrace 113. To be fixed.

The protective tape 160 may be adhered to the front of the protective circuit module 120 and the case holder 140. In addition, the lower region of the protective tape 160 may be adhered to the lower portion of the terrace 113, and the upper region of the protective tape 160 may be adhered to the upper portion of the battery cell 110. In this way, the protection tape 160 allows the protection circuit module 120 to be insulated from the outside.

The cover tape 170 may be attached to three side surfaces of the battery cell 110, respectively, which prevents external exposure of the battery cell 110, thereby causing an electrical short between the battery cell 110 and the external device. Do not do it.

The top tape 180 may be attached to the upper side of the battery cell 110, which protects the battery cell 110 from the external environment.

In this way, the battery pack 100 according to the embodiment of the present invention covers the connection area 131, such as protruding solder, so that the case holder 140 is insulated from the external environment, and thus, the connection area 131 It is not necessary to form a conventional ultraviolet curing protective resin coating layer.

In addition, since the battery pack 100 according to the exemplary embodiment of the present invention does not have to form the conventional cover part in the case holder 140 in the region corresponding to the connection region 131, the rigidity of the case holder 140 is weakened. Accordingly, the case holder 140 may not be damaged when the battery pack 100 is manufactured in an automated facility.

Furthermore, the battery pack 100 according to the embodiment of the present invention covers the connection region 131 of the flexible circuit board 130 formed on the protection circuit module 120 by the case holder 140, thereby providing a flexible circuit board ( When bending the 130, the stress is applied directly to the bending area (ie, the area bent in contact with the case holder 140) instead of being directly applied to the connection area 131, and thus, the connection area 131 as in the prior art. ) Cracks do not occur.

2A, 2B, and 2C are front perspective views, front views, and rear bottom perspective views of the case holder 140 used in the battery pack 100 according to an embodiment of the present invention.

As shown in FIGS. 2A, 2B, and 2C, the case holder 140 used in the battery pack 100 according to an exemplary embodiment may include a first region 141, a second region 142, The fourth region 144 connecting the third region 143, the first and

second regions

141 and 142 and the third region 143, and the first and

second regions

141 and 142, the third region 143 and the first region. It may include a fifth region 145 connecting the four regions 144.

The case holder 140 may be manufactured integrally by a thin film injection process using an insulating resin as described above, and may be manufactured in various processes. Here, the case holder 140 is, for example, but not limited to, polyvinyl chloride resin, polystyrene resin, polyethylene resin, polypropylene resin, acrylic resin, nylon, phenol resin, amino resin, epoxy resin, silicone resin and the like. It may be formed of the same synthetic resin.

The first region 141 has an approximately flat upper surface 141a and an approximately flat lower surface 141b opposite thereto, which covers one surface (eg, the upper surface) of the protection circuit module 120 and also has a first thickness. Have The first region 141 may further include a plurality of protrusions 141c for pressing the protective circuit module 120 toward the third region 143 toward the lower side. In addition, the first region 141 may further include a first skin portion 141d formed to allow a test probe (not shown) to easily access the test pad 124 provided in the protection circuit module 120. have. The first region 141 may have a thickness of about 0.2 mm to about 0.4 mm, for example, but not limited thereto.

The second region 142 covers the connection region 131 such as protruding solder or solder, which has a second thickness smaller than the first thickness. For example, the second region 142 also includes a flat upper surface 142a and a lower surface 142b which is the opposite surface, and the upper surface 142a of the second region 142 is the upper surface 141a of the first region 141. ) And a bottom surface 142b of the second region 142 has a plane different from the bottom surface 141b of the first region 141. For example, the lower surface 142b of the second region 142 may be higher than the lower surface 141b of the first region 141. As another example, the height from the third region 143 to the lower surface 142b of the second region 142 may be higher than the height from the third region 143 to the lower surface 141b of the first region 141. have.

In this way, the protruding connection region 131 connecting the flexible circuit board 130 to the protection circuit module 120 can be easily positioned under the second region 142. Due to the structure of the second region 142, the second region 142 of the case holder 140 does not protrude convexly upward by the connection region 131 of the flexible circuit board 130. The second region 142 may have, for example, a thickness of about 0.1 mm to about 0.2 mm, although not limited thereto.

The third region 143 includes an approximately flat upper surface 143a and a flat lower surface 143b which is the opposite surface thereof, and covers the other surface (eg, the lower surface) of the protection circuit module 120. In addition, the third region 143 may include a third hide 143d formed in an area corresponding to the cell tab 112. For example, the third region 143 is a region corresponding to the positive cell tab 112a of the PCM positive electrode conductive tab 122a and the battery cell 110, and the negative electrode of the PCM negative electrode conductive tab 122b and the battery cell 110. Third cover portions 143d may be formed in regions corresponding to the cell tabs 112b. In addition, the third skin 143d may extend to not only the third region 143 but also a portion of the fourth region 144. Therefore, in the process of connecting the positive cell tab 112a and the negative cell tab 112b to the PCM positive electrode conductive tab 122a and the PCM negative electrode conductive tab 122b, respectively, the third region 143 and / or the fourth region 144. ) Does not interfere with this connection process. Here, the thickness of the third region 143 may have a value between the thickness of the first region 141 and the thickness of the second region 142. For example, the thickness of the first region 131 may be the thickest, the thickness of the third region 143 may be thick, and the thickness of the second region 142 may be the thinnest.

In addition, the fourth region 144 connects the first and

second regions

141 and 142 and the third region 143 to each other, and is generally formed on the rear surface of the protection circuit module 120. Thus, the rear of the protection circuit module 120 is not in electrical contact with the battery cell 110.

In addition, the fifth region 145 connects the first and

second regions

141 and 142, the third region 143, and the fourth region 144, and is generally formed thickest on both sides of the protection circuit module 120. . Accordingly, both sides of the protection circuit module 120 are not electrically contacted with the battery cell 110, and the fifth region 145 reinforces the rigidity of the case holder 140.

By such a configuration, the connection region 131 of the protective circuit module 120 and the flexible circuit board 130 connected thereto can be stably coupled to the case holder 140. In this case, since the front of the case holder 140 is all open, the front surface of the protection circuit module 120 may also be opened, and the flexible circuit board 130 may also extend a predetermined length toward the front.

In this way, the battery pack 100 according to the embodiment of the present invention, in the case holder 140, by the second region 142 of the case holder 140 having a second thickness smaller than the first thickness, The protruding connection region 131 is covered with the second region 142 without interfering with the second region 142 and is easily coupled / positioned in the case holder 140. In addition, the protection circuit module 120 may be protected and insulated from the external environment by the first region 141 of the case holder 140 having the thickest first thickness. In addition, the thickness of the battery pack 100 may be kept thin by the third region 143 of the case holder 140 having the thinnest third thickness.

3A and 3B are perspective views and cross-sectional views illustrating a relationship between the protection circuit module 120, the flexible circuit board 130, and the case holder 140 in the battery pack 100 according to an embodiment of the present invention. 3C is a perspective view illustrating a bent state of the flexible circuit board 130.

3A, 3B, and 3C, one end of the flexible circuit board 130 may be electrically connected to the hard circuit board 121 of the protection circuit module 120 through a connection area 131 such as soldering or soldering. Can be connected to.

Here, the connection area 131 has a shape that protrudes convexly toward the top. However, since the second thickness of the second region 142 of the case holder 140 covering the connection region 131 is formed relatively thinner than the first thickness of the first region 141, the projected connection region 131 does not interfere with the second region 142 and does not convexly deform the second region 142. For example, the upper surface 142a of the second region 142 may be coplanar with the upper surface 141a of the first region 141.

In addition, a plurality of electronic components 123 may be mounted on a lower surface of the hard circuit board 121 of the protection circuit module 120 to perform battery protection. The electronic components 123 may include a case holder 140. ) May be close to or in close contact with the third region 143.

On the other hand, in the case holder 140, the edge 142e of the second region 142 is formed outside the edge of the connection region 131. For example, in the related art, an escape area is formed in the second area 142 corresponding to the connection area 131. However, in an embodiment of the present invention, the edge area of the second area 142 is provided instead of the escape area. 142e is formed outside the edge of the connection area 131.

Accordingly, as shown in FIG. 3C, the edge 142e of the second region 142 of the case holder 140 is formed outside the edge of the connection region 131, so that the flexible circuit board 130 faces upward. When bent, the stress is applied directly to one region of the flexible circuit board 130 outside the stress instead of being directly applied to the connection region 131, thereby preventing cracking of the connection region 131. For example, since the bent region is formed at a portion in contact with the edge 142e of the second region 142 when the flexible circuit board 130 is bent, stress is applied to the bent region without being applied to the connection region 131. . Accordingly, since stress is not directly applied to the connection area 131, a crack phenomenon of the connection area 131 may be prevented.

4A, 4B, and 4C are plan views illustrating a relationship between the protection circuit module 120, the flexible circuit board 130, and the case holder 140 in the battery pack 100 according to an embodiment of the present invention; Front view and bottom view.

As shown in FIG. 4A, the first region 141 of the case holder 140 may be formed in a semi-circular shape so that the probe may easily access the test pad 124 formed on the upper surface of the rigid circuit board 121. And a second cover 141d, and the second region 142 of the case holder 140 completely covers the connection region 131 that connects the flexible circuit board 130 to the upper surface of the rigid circuit board 121. Form. In particular, the edge 142e of the second region 142 is positioned outside of the edge of the connection region 131, and the edge 142e of the second region 142 is positioned relative to the edge of the first region 141. Approximately parallel.

As shown in FIG. 4B, a plurality of electronic components 123 for performing a protection operation are mounted on a lower surface of the rigid circuit board 121, and the electronic components 123 generally have a third region (ie, a case holder 140). 143). In addition, a PCM positive electrode conductive tab 122a and a PCM negative electrode conductive tab 122b may be provided on the bottom surface of the hard circuit board 121. An example of the cell tab 112 of the battery cell 110 is connected to the PCM cathode conductive tab 122a and the PCM cathode conductive tab 122b, and the anode cell tab 112a and the cathode cell tab 112b of the battery cell 110 are connected to each other. Can be. Accordingly, the third cover 143d may be formed in the third region 143 of the case holder 140 in the region corresponding to the PCM positive electrode conductive tab 122a and the PCM negative electrode conductive tab 122b.

As shown in FIG. 4C, a third cover 143d may be formed over the third region 143 and the fourth region 144 of the case holder 140.

Meanwhile, the case holder 140 has the first region 141, the third region 143, and the fourth region 144 integrally connected to each other through the fifth region 145 formed at both sides thereof, thereby securing a certain strength. Done.

In this way, the case holder 140 does not have a wide escape portion as in the prior art in a region corresponding to the connection region 131 of the flexible circuit board 130, thereby securing strength of a predetermined value or more, and thus the case holder 140. ) Are not damaged when handled in automated equipment for battery pack manufacturing. In addition, the case holder 140 may include a first cover 141d formed in an area corresponding to the test pad 124 to allow the test probe to easily access the test pad 124. In addition, the case holder 140 may include the third tab 143d formed in a region corresponding to the PCM positive electrode conductive tab 122a and the PCM negative electrode conductive tab 122b, and thus the cell tab 112 of the battery cell 110 may be formed. For example, the welding process of the anode cell tab 112a and the cathode cell tab 112b is facilitated.

5A and 5B are perspective views and cross-sectional views illustrating a relationship between the protection circuit module 120, the flexible circuit board 130, and the case holder 240 in the battery pack 100 according to another embodiment of the present invention. 5C is a perspective view illustrating a bent state of the flexible circuit board 130.

As illustrated in FIGS. 5A, 5B, and 5C, the case holder 240 may include a protrusion 241 in which the second region 242 protrudes outward from the first region 141. For example, the edge 241e of the second region 242 may be formed outside the edge of the first region 141. Of course, the configuration in which the second thickness of the second region 242 is thinner than the first thickness of the first region 141 is the same as described above.

Accordingly, as shown in FIG. 5C, the edge 241e of the protrusion 241 of the second region 242 of the case holder 240 is formed outside the edge of the connection region 131, thereby providing a flexible circuit board. When the 130 is bent upward, stress is applied to an area of the flexible circuit board 130 outside of the connection area 131, so that the crack of the connection area 131 can be prevented. have. For example, since the bent region is formed at a portion in contact with the edge 241e of the protrusion 241 of the second region 242 when the flexible circuit board 130 is bent, stress is not applied to the connection region 131. It is applied to the bending area. Accordingly, since stress is not directly applied to the connection area 131, a crack phenomenon of the connection area 131 may be prevented.

6A, 6B, and 6C are plan views illustrating a relationship between the protection circuit module 120, the flexible circuit board 130, and the case holder 240 in the battery pack 100 according to another embodiment of the present invention; Front view and bottom view.

As illustrated in FIGS. 6A, 6B, and 6C, the case holder 240 may include a protrusion 241 in the second region 242, which is relatively thinner than the first region 141. The edge 241e of the protrusion 241 protrudes outward from the edges of the first region 141 and the third region 143.

Therefore, when the flexible circuit board 130 is bent, a stress is applied to a predetermined region of the flexible circuit board 130 corresponding to the edge 241e of the protrusion 241 to be bent, thereby connecting the flexible circuit board 130. The stress is not applied to the region 131. Of course, a crack phenomenon of the connection region 131 can be prevented accordingly.

Hereinafter, a manufacturing method of the battery pack 100 having the above-described configuration will be described.

7A and 7B illustrate an electrical connection state between the battery cell 110 and the protection circuit module 120 in the method of manufacturing the battery pack 100 according to an embodiment of the present invention.

As shown in FIGS. 7A and 7B, the flexible circuit board 130 is connected to the rigid circuit board 121 constituting the protective circuit module 120 through a connection area 131 such as soldering or soldering. The case holder 140 may be supplied in a state in which the case holder 140 is coupled to the protection circuit module 120. In addition, the PCM cathode conductive tab 122a and the PCM cathode conductive tab 122b provided in the protection circuit module 120 may be supplied in a state before being bent. Therefore, the case holder 140 and the protection circuit module 120 may be supplied in a form substantially standing relative to the battery cell 110. For example, the flexible circuit board 130 coupled to the protection circuit module 120 may be supplied in a downward direction.

The positive cell tab 112a and the negative cell tab 112b of the battery cell 110 are connected to the PCM positive conductive tab 122a and the PCM negative conductive tab 122b of the protection circuit module 120 to which the case holder 140 is coupled. For example, but not limited to, laser welding, ultrasonic welding or resistance welding may be performed respectively.

8A and 8B illustrate a state in which the

tabs

122a and 122b of the protection circuit module 120 are bent in the manufacturing method of the battery pack 100 according to an exemplary embodiment of the present invention.

As shown in FIGS. 8A and 8B, the case holder 140 and the protection circuit module 120 coupled to each other by rotating the PCM positive electrode conductive tab 122a and the PCM negative electrode conductive tab 122b by approximately 90 degrees. It may be in a state substantially parallel to the cell (110). In this way, the flexible printed circuit board 130 may be positioned substantially below the battery cell 110. In addition, the insulating tape 150 bent in a substantially "┛" shape may be attached onto the terrace 113 of the battery cell 110.

9A and 9B illustrate a bending state of the

cell tabs

112a and 112b in the method of manufacturing the battery pack 100 according to an exemplary embodiment of the present invention.

9A and 9B, the positive electrode tab 112a and the negative cell tab 112b extending from the battery cell 110 are bent by approximately 180 degrees, such that the case holder 140 and the protection circuit module (140) are mutually coupled to each other. 120 may be seated on the terrace 113 of the battery cell 110. In this case, since the insulating tape 150 is already attached to the terrace 113, the case holder 140 (eg, the third region 143) may be adhered to the insulating tape 150. In this manner, the flexible circuit board 130 extends outward through the front of the battery cell 110.

10A and 10B are diagrams illustrating a tape attachment state in a method of manufacturing the battery pack 100 according to an embodiment of the present invention.

10A and 10B, the protective tape 160 covers the case holder 140 and the protective circuit module 120 exposed through the case holder 140. Of course, at this time, the flexible circuit board 130 still has a predetermined length extending outward from the protection circuit module 120.

What has been described above is only one embodiment for carrying out a battery pack according to the present invention, and the present invention is not limited to the above-described embodiment, and the present invention deviates from the gist of the present invention as claimed in the following claims. Without this, anyone skilled in the art to which the present invention pertains will have the technical spirit of the present invention to the extent that various modifications can be made.

Claims

A battery cell having a cell tab;

A protection circuit module electrically connected to the cell tab;

A flexible circuit board electrically connected to the protection circuit module through a connection area; And

A case holder covering the protective circuit module and the connection region,

The case holder is a battery pack, the thickness of the region corresponding to the connection region is thinner than the thickness of the region corresponding to the outside of the connection region.
The method of claim 1,

The case holder is

A first region corresponding to one surface of the protection circuit module and having a first thickness;

A second region corresponding to the connection region and having a second thickness smaller than the first thickness; And

And a third region corresponding to the other surface of the protection circuit module and having a third thickness between the first thickness and the second thickness.
The method of claim 2,

The first and second regions each have a flat upper surface and a flat lower surface as opposite surfaces of the upper surface, respectively.

An upper surface of the first and second regions may be the same surface, and a lower surface of the first and second regions may be different surface.
The method of claim 2,

And the connection area comprises solder.
The method of claim 2,

The edge of the second region is a battery pack formed on the outer side than the edge of the connection region.
The method of claim 2,

The first region of the case holder includes a first escape portion formed in an area corresponding to the test pad formed in the protective circuit module.
The method of claim 2,

The third region of the case holder includes a third cover portion formed in an area corresponding to the cell tab.
The method of claim 2,

The second region includes a protrusion that protrudes outward more than the first region.
The method of claim 2,

The battery tab of the battery cell is bent so that the third region of the case holder is bonded to the terrace of the battery cell through an adhesive tape.