JP2014022287A - Flexible printed substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible printed substrate capable of performing deformation in response to shape distortion of a battery pack due to a difference in an interval between single cells and suppressing generation of damage such as cracks.SOLUTION: A flexible printed substrate 101 to be attached to a battery pack constituted of aligning a plurality of single cells includes cut portions 3a, 3b arranged so as to cross upper surfaces of the plurality of single cells along an alignment direction of the plurality of single cells, formed like bands of which the longitudinal direction is set to the alignment direction of the plurality of single cells and extended in a width direction. The cut portions include the first cut portion 3a extended from one side end Sto the other side end Sand the second cut portion 3b extended from the other side end Sto the one-side end S. It is also available that the cut portions 3a, 3b are alternately formed along the longitudinal direction or arranged on approximately identical positions in the longitudinal direction.

Description

  The present invention relates to a flexible printed circuit board. More specifically, the present invention is used for an assembled battery in which a plurality of unit cells are arranged, and deforms following the shape distortion of the assembled battery due to a variation in the interval between the unit cells, and damage such as cracks. The present invention relates to a flexible printed circuit board that can prevent the occurrence of the above.

Conventionally, an assembled battery is known in which a plurality of unit cells are combined, electrodes of these unit cells are electrically connected and integrated. This assembled battery is used as a power source in fields related to automobiles such as electric cars and hybrid cars. A flexible printed circuit board may be attached to such an assembled battery. The mounting method is, for example,
The positive electrode connecting portion and the negative electrode connecting portion on both edges of the flexible printed board are connected to the positive electrode and the negative electrode of the battery, respectively (for example, see Patent Document 1).

JP 2003-45409 A

  However, in the power supply device described in Patent Document 1, no attention is paid to the shape distortion of the assembled battery due to the variation in the interval between the plurality of batteries. For this reason, there is a risk that the flexible printed circuit board may be deformed or cracked due to the shape distortion of the assembled battery.

  The present invention has been made in view of the above-described conventional situation, and an object thereof is to reduce deformation, cracks, and the like of a flexible printed circuit board due to shape distortion of an assembled battery.

The present invention is as follows.
1. A flexible printed circuit board attached to an assembled battery in which a plurality of single cells are arranged,
Along the alignment direction of the plurality of unit cells, arranged to cross the upper surface of the plurality of unit cells,
While forming a strip shape in which the alignment direction of the plurality of single cells is a longitudinal direction,
A flexible printed circuit board provided with a cut portion extending in the width direction.
2. The cut portion includes a first cut portion that extends from one side end to the other side end, and a second cut portion that extends from the other side end to the one side end,
The first cut portions and the second cut portions are alternately provided along the longitudinal direction. A flexible printed circuit board according to 1.
3. The sum of the depth of cut from the one side end of the first cut portion and the depth of cut from the other side end of the second cut portion is larger than the width dimension. A flexible printed circuit board according to 1.
4). The cut portion is provided so as to be located at a boundary portion between the plurality of unit cells arranged in line. A flexible printed circuit board according to 1.
5. The cut portion includes a first cut portion that extends from one side end to the other side end, and a second cut portion that extends from the other side end to the one side end,
The first cut portion and the second cut portion are provided at substantially the same position in the longitudinal direction. A flexible printed circuit board according to 1.
6). 1. The tip of the notch is rounded. To 5. The flexible printed circuit board of any one of these.

The flexible printed circuit board according to the present invention has a strip shape in which the alignment direction of the plurality of single cells is a longitudinal direction, and is provided with a cut portion extending in the width direction. Therefore, the battery deforms easily following the shape distortion of the assembled battery due to the variation in the interval between the plurality of single cells. As a result, damage such as cracks is prevented or at least suppressed.
The cut portion includes a first cut portion that extends from one side end to the other side end, and a second cut portion that extends from the other side end to the one side end. When the cut portions and the second cut portions are alternately provided along the longitudinal direction, the following effects are obtained. That is, it can be more easily deformed to one side end side and to the other side end side. Therefore, regardless of the direction of shape distortion of the assembled battery, it is possible to obtain a flexible printed board that easily follows and deforms and does not cause damage such as cracks.
Further, in the above 2. In the present invention, when the sum of the depth of cut from one side end of the first cut portion and the depth of cut from the other side end of the second cut portion is larger than the width dimension, the following effects are obtained: There is. That is, even when the flexible printed circuit board is more easily deformed and the shape distortion such as the variation between the single cells is larger, the flexible printed circuit board can be easily followed by the shape distortion and deformed to prevent damage such as a crack.
In addition, the 3. In the invention, when the notch is provided so as to be located at the boundary between the plurality of aligned single cells, the electrodes of the adjacent single cells are not connected by the bus bar, The flexible printed circuit board can be easily deformed by following the shape distortion on the side where the interval is particularly easy to expand, and does not cause damage such as cracks.
Further, the cut portion includes a first cut portion configured to extend from one side end to the other side end and a second cut portion configured to extend from the other side end to the one side end. When the cut portion and the second cut portion are provided at substantially the same position in the longitudinal direction, the following effects are obtained. That is, it is easy to secure an arrangement place for an IC chip or the like on the surface of the flexible printed board.
In addition, when the tip of the cut portion is rounded, stress concentration on the tip portion can be prevented, and a flexible printed circuit board that is less susceptible to damage such as cracking at the tip portion of the cut portion can be obtained. it can.

The present invention is further illustrated by the following detailed description with reference to a number of referenced drawings, given non-limiting examples of exemplary embodiments according to the present invention, wherein like reference numerals denote Similar parts are represented through these figures.
It is a perspective view which exploded and represents the assembled battery and the conventional flexible printed circuit board etc. which are used by attaching to this assembled battery. It is a front view of the flexible printed circuit board in which the 1st and 2nd cut part is provided alternately along the longitudinal direction, and the cut of each cut part is deep. In FIG. 2, it is a front view of the flexible printed circuit board in which the notch of each notch part is shallow. It is a front view of the assembled battery with which the flexible printed circuit board of FIG. 2 was attached. It is a front view of the flexible printed circuit board in which the 1st and 2nd cut part is provided in the substantially the same position of the longitudinal direction, and the cut of each cut part is shallow. In FIG. 5, it is a front view of the flexible printed circuit board with the deep notch of each notch part. It is a front view of the assembled battery with which the flexible printed circuit board of FIG. 5 was attached. It is explanatory drawing which compares and shows the notch part which the front end is rounded, and the notch part which a front end has a corner | angular part.

Hereinafter, the present invention will be described in detail with reference to the drawings.
The items shown here are exemplary and illustrative of the embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

  Flexible printed circuit boards (hereinafter abbreviated as “FPC”) 101 to 104 of the present invention are FPCs that are used by being attached to an assembled battery 200 in which a plurality of single cells 20 are arranged. Further, the FPC is arranged so as to cross the upper surface of the plurality of unit cells 20 along the alignment direction of the plurality of unit cells 20, and forms a strip shape in which the alignment direction of the plurality of unit cells 20 is a longitudinal direction. The cut portions 3a and 3b extending in the width direction are provided (see, for example, FIGS. 2, 3 and 5, 6).

  FIG. 1 is a perspective view of an assembled battery 200 and a conventional FPC 100 used by being attached to the assembled battery 200. The FPCs 101 to 104 of the present invention have the same configuration as the conventional FPC 100 except that the notches 3a and 3b are provided, and are used by being attached to the assembled battery 200 in exactly the same manner. Further, in the FPC 100 of FIG. 1, wiring 5 for measuring the voltage of each unit cell 20 and the like is arranged inside. And the wiring 5 and the positive electrode 20a and the negative electrode 20b are electrically connected by inserting the through-hole 2a provided in the connection part 2 of the FPC 100 into the positive electrode 20a and the negative electrode 20b of each unit cell 20. It has become. In the FPCs 101 to 104 of the present invention, wirings are arranged in the same manner, and the wirings and the respective electrodes are connected in the same manner, but the illustration of the wirings is omitted in FIGS.

[1] As the incisions incisions, a first notch portion 3a of the embodiment extending from one side end _{S 1} of the width direction of FPC101~104 to the other side edge _{S 2,} the other in the width direction of FPC101~104 a second cut portion 3b form extending from a side edge S ₂ to one side edge S ₁ is provided. Each of the FPCs 101 to 104 includes a main body 1 and a connection portion 2 provided so as to protrude to both sides of the main body 1. Furthermore, one side edge S ₁ is the outer end of the connecting portion 2 which protrudes from the main body portion 1 to the one side, the other side edge S ₁ from the main body portion 1 to the other side is the outer end of the connecting portion 2 that protrudes (for one side end _{S 1} and the other side edge _{S 2,} at 2, 3 and 5 and 6, the dashed line connecting the connecting portion 2 of the 101 to 104 reference).

  The FPCs 101 to 104 are used by fitting the through holes 2 a provided in the connection portion 2 described above into the positive electrode 20 a and the negative electrode 20 b of each unit cell 20. Further, the bus bar 4 is similarly fitted into the positive electrode 20a and the negative electrode 20b of each unit cell 20 from the upper surface of the FPCs 101 to 104. Then, the FPCs 101 to 104 are fixed together with the bus bar 4 to the assembled battery 200 by screwing nuts 6 and the like from the upper surface of the bus bar 4 to the outer periphery of each positive electrode 20a and negative electrode 20b. As described above, in the FPCs 101 to 104, the through-hole 2a is fitted into the positive electrode 20a and the negative electrode 20b of each unit cell 20, and the wiring 5 (see FIG. 1) provided in the FPCs 101 to 104 is each unit cell 20. Are electrically connected to the positive electrode 20a and the negative electrode 20b, and the voltage of each unit cell 20 is measured.

The notches 3a and 3b have various forms, each having its own characteristics. Hereinafter, the notches 3a and 3b will be described in detail.
(1) Form in which the first and second cut portions are alternately provided along the alignment direction of the single cells. The first cut portions 3a and the second cut portions 3b are longitudinal directions that are the alignment directions of the single cells 20. It can be set as the form provided alternately along the direction (refer FIG. 2, 3). In such a form, the FPCs 101 and 102 are easily deformed following the distortion in any direction in the width direction regardless of the position where the shape distortion of the assembled battery 200 occurs, and the FPCs 101 and 102 are cracked. Damage such as the occurrence of spillage is sufficiently suppressed.

Cut portions 3a of the above-described embodiment, when the 3b, each of the cut depth of the first cut portion 3a and the second cut portion 3b, in other words, one side end of FPC101,102 _{S 1} or the other side edge _{S 2} The length in the width direction from is not particularly limited. Further, a notch depth from one side end _{S 1} of the FPC101,102 the first cut portion 3a, a slit depth from the other side edge _{S 2} of FPC101,102 the second cut portion 3b, the sum of, It may be larger than the width dimension of the FPCs 101 and 102, may be substantially the same, or may be smaller.

  When the total depth of cut of the first and second cut portions 3a and 3b is equal to or greater than the width dimension of the FPCs 101 and 102, the FPCs 101 and 102 follow the shape distortion of the assembled battery 200 in any direction in the width direction. Is also preferable because it can be easily deformed and damage such as cracks can be more sufficiently suppressed. However, since the strength of the FPCs 101 and 102 may be reduced, the depth of each of the first and second notches 3a and 3b is 50 to 80%, particularly 60 to 70% of the width dimension of the FPCs 101 and 102. Preferably there is.

  On the other hand, if the total depth of cut of the first and second cut portions 3a and 3b is smaller than the width dimension of the FPCs 101 and 102, there is no problem in terms of strength of the FPCs 101 and 102, but the shape distortion of the assembled battery 200 is followed. From the viewpoint of deformation, the FPCs 101 and 102 may be damaged such as cracks. Therefore, the cut depth of each of the first and second cut portions 3a and 3b is preferably 20 to 45%, particularly 35 to 45%, of the width dimension of the FPCs 101 and 102.

  In addition, the first cut portion 3a and the second cut portion are both in the case where the sum of the cut depths of the first and second cut portions 3a and 3b is larger than, substantially the same as, or smaller than the width dimension of the FPCs 101 and 102. Each of the depths of cut with 3b may be substantially the same or different. However, in any case where the total depth of the first and second cut portions 3a and 3b is larger than, substantially the same as, or smaller than the width dimension of the FPCs 101 and 102, the first and second cut portions 3a and 3b. It is preferable that there is no great difference in the depth of cut.

  For example, the FPCs 101 and 102 in which one side is a deep cut portion 3a or 3b exceeding 90%, particularly 95% of the width dimension, are not preferable in terms of strength. The depth of each of the first and second cut portions 3a and 3b is preferably 0.7 to 1.3, particularly preferably 0.8 to 1.2, when one is set to 1. Also, approximately 1, that is, the first cut portion 3a and the second cut portion 3b may have substantially the same cut depth. When the total depth of cut of the first and second cut portions 3a and 3b is smaller than the width dimension of the FPCs 101 and 102, there is a large difference in the depth of cut unless the cut depth is extremely deep as described above. However, there is no problem in terms of strength. However, this is not preferable from the viewpoint of ease of deformation in both the width directions due to the shape distortion of the assembled battery 200.

  Furthermore, when the 1st notch part 3a and the 2nd notch part 3b are the forms provided alternately along the longitudinal direction which is the alignment direction of the cell 20, the 1st and 2nd notch parts 3a, 3b Is preferably provided so as to be located at the boundary between the plurality of aligned unit cells 20. Thereby, when shape distortion arises between the adjacent unit cells 20, damage to the FPCs 101 and 102 can be easily suppressed. Further, in this case, the first and second cut portions 3 a and 3 b are located at a boundary portion where the positive electrode 20 a and the negative electrode 20 b of the adjacent single cells 20 are not connected by the bus bar 4 among the boundary portions of the single cells 20. It is particularly preferable to provide such a configuration (see FIG. 4). If the positive electrode 20a and the negative electrode 20b of the adjacent unit cells 20 are connected by the bus bar 4, the distortion between the unit cells 20 is difficult to occur, but distortion between the electrodes not connected by the bus bar 4 is difficult. It is because it is easy to occur.

  As described above, in the embodiment in which the first cut portions 3a and the second cut portions 3b are alternately provided along the longitudinal direction that is the alignment direction of the unit cells 20, the first and second cut portions 3a are provided. 3b is not less than the width dimension of the FPCs 101 and 102, and is preferably 50 to 80%, particularly 60 to 70% of the width dimension. Further, it is more preferable that the first cut portion 3a and the second cut portion 3b have substantially the same cut depth. Further, the first and second cut portions 3 a and 3 b are located at the boundary portion where the positive electrode 20 a and the negative electrode 20 b of the adjacent single cells 20 are not connected by the bus bar 4 among the boundary portions of the single cells 20. It is particularly preferred that it is provided.

Moreover, it is preferable that the 1st cut | notch part 3a and the 2nd cut | notch part 3b are rounded the front end irrespective of the position provided in FPC101,102, the depth of a notch, etc. If the tip is rounded, it is possible to suppress the formation of a tear at the tip of the first and second cut portions 3a and 3b due to stress concentration compared to the case where the tip has a corner (the rounded tip in FIG. 8). (Refer the front-end | tip part 3d which has the part 3c and a corner | angular part).
The first cut portion 3a and the second cut portion 3b are usually provided in a direction substantially perpendicular to the longitudinal direction of the FPCs 101 and 102, and even when provided in an oblique direction, It is preferable that the angle is 80 to 100 °, particularly 85 to 95 °.

(2) A configuration in which the first and second cut portions are provided at substantially the same position in the longitudinal direction along the alignment direction of the unit cells. As described above, the cut portion includes the first cut portion 3a and the first cut portion 2 cut portions 3b, and the first cut portions 3a and the second cut portions 3b can be provided at substantially the same position in the longitudinal direction, which is the alignment direction of the unit cells 20 (FIG. 5 and 6). In the case of such a configuration, as in the configuration described in (1) above, when shape distortion occurs in the assembled battery 20, the FPCs 103 and 104 follow the distortion in any direction in the width direction. Thus, damage such as cracks in the FPCs 103 and 104 is suppressed.

Further, as described above, when the first and second cut portions 3a and 3b are provided at substantially the same position in the longitudinal direction of the FPCs 103 and 104, each of the first cut portion 3a and the second cut portion 3b. cut depth, in other words, the length in the width direction from the side end _{S 1} or the other side edge _{S 2} of FPC103,104 one hand, the sum is less than the width dimension is maintained the strength of FPC103,104 As long as it is not particularly limited.

  In addition, the depth of cut of each of the first cut portion 3a and the second cut portion 3b may be substantially the same or different, but it is preferable that there is no great difference. For example, the FPCs 103 and 104 in which one of them has a deep cut portion exceeding 90%, particularly 95% of the width dimension is not preferable from the viewpoint of strength. The depth of each of the first and second cut portions 3a and 3b is preferably 0.7 to 1.3, particularly preferably 0.8 to 1.2, when one is set to 1. May also be approximately 1, that is, substantially the same depth of cut.

  Although the sum total of the cut depth of 1st and 2nd cut part 3a, 3b is not specifically limited, It is preferable that it is 50 to 80% of the width dimension of FPC103,104, especially 60 to 70%. If the total depth of cut of the first and second cut portions 3a and 3b is 50 to 80%, the FPC 103 and 104 may be damaged such as cracks due to deformation following the shape distortion of the assembled battery 200. It can be suppressed. Furthermore, the total depth of cut can be as small as 60% or less, and can be particularly less than 50%. Thus, when the total depth of cut is small, the ease of deformation following the shape distortion of the assembled battery 200 may not always be sufficient, but it is easy to mount an IC chip or the like on the FPCs 103 and 104. This is preferable.

The depths of the first and second cut portions 3a and 3b are substantially the same, and the sum of the cut depths of the first and second cut portions 3a and 3b is 60% or less, particularly less than 50%. Is smaller from the viewpoint that a surface for stably mounting an IC chip or the like can be secured sufficiently at the center in the width direction of the FPCs 103 and 104 (see FIG. 7).
In the case of this embodiment, the first and second cut portions 3a and 3b are rounded at the tips as in the case of (1), regardless of the positions provided in the FPCs 103 and 104, the depth of the cut, and the like. It is preferable that Further, as in the case of (1), the first and second cut portions 3a and 3b are normally provided in a direction substantially perpendicular to the longitudinal direction of the FPCs 101 and 102.

[2] Material of FPC and type of unit cell, etc. The material of the FPCs 101 to 104 used by being attached to the assembled battery 200 is not particularly limited, but usually a polyimide having high heat resistance, high mechanical strength and easy to mold. Used. Further, the thickness of the FPCs 101 to 104 is 12.5 to 25 μm, and is often a substantially constant thickness. For example, for the purpose of mounting an IC chip or the like, a predetermined portion is provided if necessary. It can also be thickened.

  The kind of the unit cell 20 which comprises the assembled battery 200 is not specifically limited, Various well-known unit cells 20 can be used. As this single battery 20, secondary batteries, such as a lithium ion battery, a nickel hydride battery, and a nickel cadmium battery, and various primary batteries are mentioned, for example. The assembled battery 200 is configured by arranging a plurality of these unit cells 20 in a predetermined direction. More specifically, the positive electrode 20a and the negative electrode 20b of the adjacent unit cells 20 are arranged so as to be close to each other, the adjacent positive electrode 20a and the negative electrode 20b are sequentially connected by the bus bar 4, and all the single cells 20 are connected in series. They are connected (see FIGS. 4 and 7).

  It should be noted that the above examples are for illustrative purposes only and are not to be construed as limiting the invention. Although the invention has been described with reference to exemplary embodiments, it is to be understood that the language used in the description and illustration of the invention is illustrative and exemplary rather than limiting. As detailed herein, changes may be made in its form within the scope of the appended claims without departing from the scope or spirit of the invention. Although specific structures, materials and examples have been referred to in the detailed description of the invention herein, it is not intended to limit the invention to the disclosure herein, but rather, the invention is claimed. It covers all functionally equivalent structures, methods and uses within the scope.

  The FPC of the present invention can be used for an assembled battery in which various single cells are arranged. When a shape distortion occurs in the assembled battery, the FPC easily follows the distortion and deforms, and a crack occurs. Can be suitably used in power supply applications in a wide range of technical fields such as automobile-related fields and home appliance-related fields.

100, 101, 102, 103, 104; FPC, 200, 201, 202; assembled battery, 20; single cell, 20a; positive electrode, 20b; negative electrode, 1; main body of FPC, S ₁ ; one side edge, S ₂ ; other side end, 3a, 3b; cut portion, 3c; rounded tip portion of cut portion, 3d; tip portion having a corner portion of the cut portion, 4; bus bar, 5; wiring, E; IC chip .

Claims (6)

A flexible printed circuit board attached to an assembled battery in which a plurality of single cells are arranged,
Along the alignment direction of the plurality of unit cells, arranged to cross the upper surface of the plurality of unit cells,
While forming a strip shape in which the alignment direction of the plurality of single cells is a longitudinal direction,
A flexible printed circuit board provided with a cut portion extending in the width direction. The cut portion includes a first cut portion that extends from one side end to the other side end, and a second cut portion that extends from the other side end to the one side end,
The flexible printed circuit board according to claim 1, wherein the first cut portions and the second cut portions are alternately provided along the longitudinal direction.   The flexible of Claim 2 with which the sum total of the notch depth from the said one side end of the said 1st notch part and the notch depth from the said other side end of the said 2nd notch part is larger than a width dimension. Printed board.   The flexible printed circuit board according to claim 3, wherein the cut portion is provided so as to be located at a boundary portion between the plurality of aligned single cells. The cut portion includes a first cut portion that extends from one side end to the other side end, and a second cut portion that extends from the other side end to the one side end,
The flexible printed circuit board according to claim 1, wherein the first cut portion and the second cut portion are provided at substantially the same position in the longitudinal direction.   The flexible printed circuit board according to claim 1, wherein a tip of the cut portion is rounded.

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