JP2013058344A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack having a structure achieving high impact resistance.SOLUTION: A circuit board 17 is disposed so as to face one side surface of an outer can in a unit cell. A substrate holder 20 is inserted between the circuit board 17 and the one side surface of the outer can in the unit cell, covers a sealing plate in the unit cell, and has an L shaped appearance profile. An outer case 11 has a C shape and is attached to the unit cell covering the circuit board 17 and the substrate holder 20. In a battery pack, stripe shaped ribs 20d are erected toward the opposite side of the sealing plate on the outer side in the width direction at a portion (C portion) of the substrate holder 20 which covers the sealing plate. Stripe shaped outer edges 11g are erected toward the sealing plate side in an arm part 11b of the outer case 11. Tip parts of the ribs 20d of the substrate holder 20 are in contact with a main surface of the outer case 11.

Description

  The present invention relates to a battery pack, and more particularly, to a configuration of an exterior case.

Battery packs are used in many devices such as mobile devices such as mobile phones or vehicles such as electric assist bicycles and electric cars. As an example, a configuration of a battery pack according to a conventional technique used for a mobile phone or the like will be described with reference to FIG.
As shown in FIG. 10, the battery pack according to the prior art includes a unit cell 95 having a flat rectangular external shape. In the unit cell 95, an exterior is configured by a bottomed rectangular tube-shaped exterior can 95a and a sealing plate 95b that seals the opening, and a negative electrode terminal 95c is projected from a part of the sealing plate 95b. The outer side of the sealing plate 95b is joined to the opening edge of the outer can 95a by laser welding or the like.

One lead plate of the PTC element 96 is connected to the negative electrode terminal 95 c of the unit cell 95. The sealing plate 95b is covered with the insulating sheet 101 except for the portion where the negative electrode terminal 95c is protruded, and the PTC element 96 sandwiches the insulating sheet 101 with respect to the sealing plate 95b. It is arranged with.
The other lead plate of the PTC element 96 is connected to the circuit board 97 via a lead plate 98 bent in an L shape. The circuit board 97 is disposed so as to face the outer surface of the side wall on the left front side in the Y-axis direction of the outer can 95a of the unit cell 95 with the substrate holder 100 interposed therebetween. An L-shaped bent lead plate 99 is also connected to the circuit board 97, and the other end of the lead plate 99 is connected to the outer surface of the bottom wall of the outer can 95 a in the unit cell 95.

  A U-shaped outer case 91 is attached to the unit cell 95 to which the PTC element 96 and the circuit board 97 are attached. The exterior case 91 is integrally formed with a main portion 91a disposed so as to cover the circuit board 97 and the like, and arm portions 91b and 91c extending from both ends thereof. The arm portion 91b is arranged so as to cover the sealing plate 95b of the unit cell 95 to which the PTC element 96 is connected, and the arm unit 91c covers the bottom wall outer surface of the outer can 95a of the unit cell 95 to which the lead plate 99 is connected. Arranged to cover.

  The battery pack is configured by adhering an exterior label 92 so as to cover the outer periphery of the unit cell 95 and the like with the outer surface of the main portion 91a of the exterior case 91 on the left front side in the Y-axis direction exposed.

JP 2009-187811 A JP 2009-43462 A JP 2008-210808 A JP 2006-147422 A

  However, in the configuration of the battery pack according to the conventional technology, when a force is applied to the outer case 91, damage may be applied to a joint portion between the outer can 95a and the sealing plate 95b in the unit cell 95. Specifically, the impact force applied to the outer case 91 is transmitted from the outer case 91 to the opening edge of the outer can 95a in the unit cell 95, and the shearing force is applied to the joint between the outer can 95a and the sealing plate 95b. Work as. In this way, when an impact force is applied from the outside, there may be a situation in which a part of the joining portion between the outer can 95a and the sealing plate 95b in the unit cell 95 is detached.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a battery pack having high impact resistance.

Therefore, the present invention adopts the following configuration.
The battery pack according to the present invention includes at least a unit cell, a circuit board, and an exterior case.
The unit cell includes a bottomed rectangular tube-shaped outer can and a sealing plate that seals the opening of the outer can.
The circuit board is disposed to face one side surface of the outer can in the unit cell.

The outer case is attached to the unit cell so as to cover the circuit board.
In the battery pack according to the present invention, in the unit cell, the sealing plate is joined to the opening edge of the outer can at the outer edge portion. In the battery pack according to the present invention, the outer case is supported at the contact portion with respect to both the outer edge portion of the sealing plate and the opening edge of the outer can, and the main surface excluding the outer edge portion of the sealing plate. Partly supported directly or indirectly.

In the battery pack according to the above prior art, the outer case is in contact only with the opening edge of the outer can, and when an impact force is applied to the outer case, the joint portion between the outer can and the sealing plate is subjected to a shearing force. There was a problem that it was transmitted and the joints were disconnected.
On the other hand, in the battery pack according to the present invention, the outer case is supported at the contact portion with respect to both the outer edge portion of the sealing plate and the opening edge portion of the outer can, and the outer edge portion of the sealing plate is Since the main surface portion is supported directly or indirectly, even when an impact force is applied to the exterior case, the force is also distributed to the main surface portion of the sealing plate. For this reason, since the damage with respect to the junction location of the exterior can of a unit cell and a sealing board can be reduced also by the impact force from the outside etc., high safety | security can be ensured.

Therefore, the battery pack according to the present invention has high impact resistance.
In the battery pack according to the present invention, for example, the following variation configuration can be adopted.
The battery pack according to the present invention further includes a substrate holder. The board holder is interposed between the circuit board and one side surface of the outer can in the unit cell. The outer case is attached to the unit cell so as to cover the substrate holder. By adopting such a configuration, the relative positioning of the circuit board with respect to the unit cell is ensured by the insertion of the substrate holder, and the reliability of the battery pack can be improved.

  The battery pack according to the present invention further includes an exterior label that covers the exterior of the exterior case, the substrate holder, the circuit board, and the unit cell in a state in which a part of the outer surface of the exterior case is exposed. And a portion inserted between the outer can of the unit cell and a portion covering the sealing plate in the unit cell are formed in an L shape, and a portion covering the sealing plate in the substrate holder In the both sides on the outer side in the width direction, ribs are erected toward the opposite side of the sealing plate, and on the side of the sealing plate on the portion corresponding to the portion of the exterior case where the ribs of the substrate holder are provided. A streak-shaped outer edge is erected toward the outer surface of the sealing plate so that the tip of the rib of the substrate holder contacts the inner main surface of the outer case. It is lifting. Further, it is possible to adopt a configuration in which the inner side surface of the outer edge of the outer case and the outer side surface of the rib in the substrate holder are in close contact with each other. As described above, when the configuration in which the rib of the substrate holder and the outer edge of the outer case are in close contact with each other is employed, the position of the outer case is regulated with respect to the substrate holder. In addition, since the substrate holder is inserted between the circuit board connected to the positive and negative terminals of the unit cell and one side surface of the outer can, the position of the substrate holder is regulated with respect to the unit cell. It has become.

Therefore, in the battery pack according to the present invention, when the above configuration is adopted, the outer case is restrained from being displaced with respect to the unit cell when the outer label is wound at the time of manufacture. When winding, it is not necessary to temporarily fix the exterior case with a double-sided adhesive tape or the like in advance, which is advantageous in terms of cost.
Further, as described above, since the outer edge of the outer case is configured to come into close contact with the rib of the substrate holder, the rigidity of the outer case is reinforced, and the outer case such as when the outer label is wound is wound. The deformation of the case can be suppressed.

  In the battery pack which concerns on this invention, the structure that the rib of a board | substrate holder has a streaky shape extended in the longitudinal direction of the part which covers a sealing board in the said structure is employable. By adopting such a configuration, the contact area between the rib in the substrate holder and the outer edge of the outer case is increased, it has high appearance quality and high impact resistance, and can suppress an increase in manufacturing cost. Can be obtained more reliably.

  The battery pack according to the present invention employs a configuration in which, in the above configuration, at least a part of the tip of the rib of the substrate holder is in contact with the inner surface of the outer case facing the sealing plate. You can also. When such a configuration is adopted, a “box section” structure is formed between the substrate holder and the outer case at the portion where the rib of the substrate holder and the outer edge of the outer case are in close contact with each other, and high rigidity is achieved. Can be secured. Therefore, when an impact force is applied to the portion of the outer case that covers the sealing plate, the load on the joint portion (welded portion) between the opening edge of the outer can and the outer edge of the sealing plate is changed to the rib of the substrate holder. And the outer edge of the outer case can be reduced, which has an effect from the viewpoint of protecting the battery pack.

Moreover, the deformation | transformation of the exterior case at the time of winding of an exterior label can be suppressed reliably.
In the battery pack according to the present invention, in the above configuration, the outer edge portion of the sealing plate rises along the opening edge portion of the outer can, and the bonding between the sealing plate and the outer can is a portion of the rising portion of the sealing plate. It is also possible to adopt a configuration that is made by welding between the end portion and the opening end edge portion of the outer can. Even in such a configuration, even when an impact force is applied to the exterior case, the force can be distributed by forming a plurality of force transmission paths. Therefore, it has high impact resistance.

  In the battery pack according to the present invention, in the above configuration, the exterior case also includes a portion that covers the bottom wall outer surface of the exterior can in the unit cell, and the portion that covers the bottom wall outer surface of the exterior can in the exterior case has a side of the exterior can. It is also possible to adopt a configuration in which streak-like ribs extending in the longitudinal direction are formed. In the case of adopting such a configuration, a portion of the outer case that covers the outer surface of the bottom wall of the outer can can have high rigidity due to the stripe-like rib formed on the outer can side. For this reason, the deformation | transformation (for example, deformation | transformation which is going to spread in a square shape) etc. can be suppressed effectively.

  In the battery pack according to the present invention, in the above-described configuration, the board holder is provided with a locking portion at a portion exposed to the side of the portion inserted between the circuit board and one side surface of the outer can in the unit cell. A latched portion is provided at a portion corresponding to the latching portion of the substrate holder in the outer case, and one of the latching portion and the latched portion is a claw portion and the other is a claw portion. It is also possible to adopt a configuration in which the hole portion receives the insertion. In the case of adopting such a configuration, the displacement of the outer case when the outer label is wound can be more reliably suppressed by the engagement between the claw portion and the hole portion.

It is a schematic perspective view which shows the external appearance structure of the battery pack 1 which concerns on Embodiment 1 of this invention. 2 is a schematic exploded perspective view showing an internal configuration of the battery pack 1. FIG. (A) is a schematic perspective view which shows the structure of the substrate holder 20, (b) is a schematic side view of the substrate holder 20, (c) is a schematic front view of the substrate holder 20. FIG. (A) is a schematic perspective view which shows the structure of the exterior case 11, (b) is a schematic top view of the exterior case 11, (c) is a schematic cross section which shows the partial cross section of the exterior case 11. It is. 3 is a schematic developed perspective view showing a relative relationship related to attachment of the outer case 11 to the core pack 10. FIG. 3 is a schematic cross-sectional view showing the positional relationship between the unit cell 15, the substrate holder 20, and the exterior case 11 in a state where the exterior case 11 is attached to the core pack 10. FIG. It is a model perspective view which shows the structure of the exterior case 31 which concerns on Embodiment 2 of this invention. It is a model expansion perspective view which shows the internal structure of the battery pack 2 which concerns on Embodiment 2 of this invention. 4 is a schematic cross-sectional view showing the positional relationship between the unit cell 35, the substrate holder 40, and the exterior case 31 in a state where the exterior case 31 is attached to the core pack 30. FIG. It is a model expansion perspective view which shows the internal structure of the battery pack which concerns on a prior art.

Below, the form for implementing this invention is demonstrated using drawing. In addition, the specific example shown below is an example used for easily explaining the configuration of the present invention and the operations and effects produced from the configuration, and the present invention is not limited to the components essential to the invention. The following specific examples are not limited at all.
[Embodiment 1]
1. External Configuration The external configuration of the battery pack 1 according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, the battery pack 1 according to the present embodiment has a flat rectangular external shape. The external appearance of the battery pack 1 includes an outer case 11 formed using a resin material and an outer label 12 that covers the entire outer periphery including a part of the outer case 11. The exterior case 11 has a submergence determination label 13 attached to the main surface on the left front side in the Y-axis direction, and the external terminals 14 are exposed from the three windows.

2. Internal Configuration The internal configuration of the battery pack 1 will be described with reference to FIG.
As shown in FIG. 2, the battery pack 1 is configured such that the outer periphery of the core pack 10 is covered with an outer case 11 and an outer label 12. The core pack 10 includes a unit cell 15 having a flat rectangular appearance, a PTC (Positive Temperature Coefficient) element 16 connected thereto, and a circuit board 17 connected to the unit cell 15 and the PTC element 16.

  The unit cell 15 has a bottomed rectangular tube-shaped outer can 15a and a sealing plate 15b that seals the opening, and the right hand of the X-axis direction is formed from the center in the Y-axis direction of the sealing plate 15b. A negative terminal 15c is projected toward the front side. The negative electrode terminal 15c is insulated from the sealing plate 15b. In the unit cell 15, the exterior excluding the negative electrode terminal 15 c, that is, the exterior can 15 a and the sealing plate 15 b are positive electrodes.

  A substrate holder 20 having an L shape in the XY direction is attached to the unit cell 15. The substrate holder 20 includes a part (hereinafter referred to as “main part”) 20a covering the sealing plate 15b of the unit cell 15 and a part (hereinafter referred to as “side part”) 20b covering one side surface of the outer can 15a in the unit cell 15. And are integrally formed. The substrate holder 20 is made of an electrically insulating material, for example, a resin material.

  One lead plate of the PTC element 16 is connected to the negative terminal 15 c through a window portion 20 c provided in the main portion 20 a of the substrate holder 20. The other lead plate in the PTC element 16 is connected to one end of a lead plate 18 bent in an L shape in the XY direction. The lead plate 18 is connected to a conductive land (not shown) of the circuit board 17 at the other end.

The circuit board 17 is provided with an external terminal 14 and the like on the main surface on the left front side in the Y-axis direction, and electronic components (not shown) constituting the circuit are mounted on the back main surface. A lead plate 19 is also connected to the circuit board 17. The lead plate 19 is connected to the outer surface of the bottom wall of the outer can 15a of the unit cell 15 at the other end.
A U-shaped outer case 11, an outer label 12, and a submergence determination label 13 are attached to the core pack 10 having the above configuration.

  The exterior case 11 is integrally formed with a main portion 11a disposed so as to cover the circuit board 17 and the like, and arm portions 11b and 11c extending from both ends thereof. The arm portion 11b is arranged so as to cover the sealing plate 15b of the unit cell 15 to which the PTC element 16 is connected, and the arm portion 11c is formed on the outer surface of the bottom wall of the outer can 15a of the unit cell 15 to which the lead plate 19 is connected. Arranged to cover. The main portion 11a of the outer case 11 is provided with a window portion 11d at each portion corresponding to the external terminal 14 of the circuit board 17, and the external terminal 14 is exposed through the window portion 11d.

Further, the main part 11a of the outer case 11 is also provided with a window part for exposing a testing point on the circuit board 17, and a submergence determination label 13 is attached to the part after the inspection.
Furthermore, a plurality of streak ribs 11 e extending in the Y-axis direction are provided on the inner surface of the arm portion 11 c of the outer case 11, that is, the surface facing the outer surface of the bottom wall of the outer can 15 a of the unit cell 15. Thereby, “warping” of the arm portion 11 c with respect to the main portion 11 a of the outer case 11 can be prevented. On the outer surfaces of the arm portions 11b and 11c, a partially bulged portion (bulged portion 11f) is provided. The bulging portion 11f corresponds to a hole 12a formed in the exterior label 12, and is exposed when the exterior label 12 is attached.

The battery pack 1 according to the present embodiment has the internal configuration as described above.
3. Configuration of Substrate Holder 20 The configuration of the substrate holder 20, which is one of the structural features of the battery pack 1 according to the present embodiment, will be described with reference to FIG.
As shown in FIG. 3A, the substrate holder 20 has a strip-shaped main portion 20a extending in the Y-axis direction and a side portion 20b extending in the X-axis direction, and is formed in an L shape as a whole. Appearance shape. The main portion 20a of the substrate holder 20 is provided with a window portion 20c corresponding to the negative electrode terminal 15c of the unit cell 15 at a substantially central portion in the longitudinal direction (Y-axis direction). In the upper part in the axial direction), ribs 20d are erected from both ends in the width direction toward the X-axis direction. That is, as shown in FIG. 3B, the height of the rib 20d is higher than the other portions of the main portion 20a.

Here, as shown in FIG. 3C, the width W ₂₀ at the portion where the rib 20 d is provided in the main portion _{20 a} is set substantially equal to the width of the sealing plate 15 b in the unit cell 15. In the unit cell 15, the sealing plate 15 b is joined to the opening edge of the outer can 15 a while being slightly recessed inward. The width W ₂₀ of the main portion 20 a of the substrate holder 20 is used as the sealing plate. By making it substantially equal to the width of 15b, when the substrate holder 20 is mounted on the unit cell 15, the movement in the width direction is restricted by the opening edge of the outer can 15a.

4). Configuration of Exterior Case 11 The configuration of the exterior case 11 that is another structural feature of the battery pack 1 according to the present embodiment will be described with reference to FIG.
As shown in FIG. 4A, the outer case 11 is formed by integrally forming a main portion 11a and two arm portions 11b and 11c, and has a U-shape as a whole. As described above, a plurality of strip-like ribs 11e extending in the Y-axis direction are provided on the inner side surface of the arm portion 11c.

  As shown in FIG. 4B, the arm portion 11b of the outer case 11 has a portion whose outer edge becomes higher inward at the tip portion (A portion). Specifically, as shown in FIG. 4 (c), the outer edge 11g is erected from both side portions at the tip portion of the arm portion 11b, and has a U-shaped cross section as a whole. The arm portion 11 b is a portion that covers the main portion 20 a of the substrate holder 20, and the outer edge 11 g is provided corresponding to the rib 20 d provided on the main portion 20 a of the substrate holder 20.

Here, as shown in FIG. 4 (c), the inner width _{W 11} between between the outer edge 11g is than the width _{W 20} of the substrate holder 20 shown in FIG. 3 (c), is slightly wider setting. For example, the inner width _{W 11} is greater than the width _{W 20,} and is 0.05 to 0.15 [mm] degree wide settings.
5. Attachment of the exterior case 11 to the core pack 10 The attachment form of the exterior case 11 to the core pack 10 is demonstrated using FIG. 5 and FIG.

As shown in FIG. 5, when the exterior case 11 is attached to the core pack 10, the main portion 11a of the exterior case 11 covers the portion on which the circuit board 17 is placed, and the arm portion 11b is the PTC element 16 or the like. Is covered, and the arm portion 11 c covers the outer surface of the bottom wall of the unit cell 15.
Here, the portion (B portion) provided with the outer edge 11g of the end portion of the arm portion 11b of the outer case 11 is covered with the portion (C portion) provided with the rib 20d of the substrate holder 20. .

As shown in FIG. 6, the main surface of the sealing plate 15b in the unit cell 15 is recessed slightly inward from the opening edge 15d of the outer can 15a. This is because the outer edge portion 15b ₁ of the sealing plate 15b is up along the opening edge 15d of the outer can 15a, as shown in a portion surrounded by a two-dot chain line, the outer can 15a and the sealing plate 15b bonding is done by the contact portion between the tip portion 15b ₂ of the outer edge portion 15b ₁ of the distal end portion 15d ₁ and the sealing plate 15b of the opening edge 15d of the outer can 15a is laser welded (welding point _{P W} ).

The bottom surface of the portion of the U-shaped cross-sectional shape of the main portion 20a of the substrate holder 20 is in contact with the outer main surface of the sealing plate 15b, also, the outer side surface 20d ₁ of the ribs 20d is the outer edge portion 15b ₁ of the sealing plate 15b It is in contact with the inner side surface.
Moreover, as shown in FIG. 6, as for the exterior case 11, the arm part 11b has covered the sealing board 15b to which the board | substrate holder 20 was attached in cap shape. Edge 11g of the outer case 11 provided in correspondence with the ribs 20d of the substrate holder 20, the inner side surface 11g ₁ are densely is (fitted in contact with the outer side surface 20d ₁ of the rib 20d of the substrate holder 20 ing). The tip portion 11g ₂ of the outer edge 11g of the outer case 11, for both of the outer edge portion 15b ₁ of the distal end portion 15b ₂ of the tip portion 15d ₁ and the sealing plate 15b of the opening edge 15d in the package can 15a of the cell 15 Are in contact.

Similarly, the rib 20 d of the substrate holder 20 is in contact with the inner main surface of the exterior case 11 at the tip portion.
Returning to FIG. 5, two locking holes are provided on the side surface of the main portion 11a of the outer case 11 (D ₁ and D ₂ portions). On the other hand, a locking claw that can be locked to the two locking holes of the outer case 11 is provided on the side portion of the substrate holder 20 on a slightly lower side surface on which the circuit board 17 is placed ( E ₁ and E ₂ parts).

  As described above, the outer case 11 is securely positioned with respect to the substrate holder 20 by the engagement between the engagement claw and the engagement hole in addition to the close contact of the outer edge 11g with the rib 20d. Is made. As shown in FIG. 6, the position of the substrate holder 20 is regulated with respect to the unit cell 15, and as a result, the position of the outer case 11 is also regulated with respect to the unit cell 15.

6). Superiority The battery pack 1 according to the present embodiment having the above-described configuration has the following advantages.
In the battery pack 1 according to the present embodiment, since the tip portion of the rib 20d in the substrate holder 20 is in contact with the inner main surface of the outer case 11, the impact force applied to the outer case 11 from the outside is Not only the joint location between the outer can 15a and the sealing plate 15b of the unit cell 15 but also the substrate holder 20 is dispersed. For this reason, since the damage with respect to the joining location of the exterior can 15a and the sealing plate 15b of the unit cell 15 can be reduced by an external impact force or the like, high safety can be ensured.

  Further, in the battery pack 1 according to the present embodiment, the rib 20 d of the substrate holder 20 and the outer edge 11 g of the outer case 11 are in close contact with each other, so that the outer case 11 is in contact with the substrate holder 20. The position is restricted. The substrate holder 20 is interposed between the circuit board 17 connected to the positive and negative terminals of the unit cell 15 and one side surface of the outer can 15a. The position is restricted. Therefore, in the battery pack 1, the outer case 11 is suppressed from being displaced with respect to the unit cell 15 when the outer label 12 is wound around the battery pack 1. For this reason, when winding the exterior label 12, it is not necessary to temporarily fix the exterior case 11 with a double-sided adhesive tape or the like in advance, which is advantageous in terms of cost.

Further, as described above, since the outer edge 11g of the outer case 11 is configured to come into close contact with the rib 20d of the substrate holder 20, the rigidity of the outer case 11 is reinforced, and the outer label 12 It is possible to suppress deformation of the outer case 11 such as during winding.
Therefore, the battery pack 1 according to the present embodiment has high impact resistance and high appearance quality, and can suppress an increase in manufacturing cost.

Further, as shown in FIG. 5, in the battery pack 1, a locking claw is provided on the substrate holder 20 (E ₁ and E ₂ portions), and a locking hole is provided in a corresponding portion of the exterior case 11 ( D ₁ and D ₂ parts). The locking claws of the substrate holder 20 are closely fitted into the locking holes of the outer case 11 and are locked together. For this reason, the position shift of the exterior case 11 at the time of winding of the exterior label 12 can be suppressed further reliably.

[Embodiment 2]
1. Configuration of Outer Case 31 The battery pack according to the second embodiment has a structural difference from the battery pack 1 according to the first embodiment, and the configuration of the outer case 31 that is the most characteristic part is shown in FIG. explain.

  As shown in FIG. 7, the exterior case 31 is formed by integrally forming a main portion 31a and two arm portions 31b and 31c, and has a U-shaped appearance as a whole. It is the same as the exterior case 11 concerning. The outer case 31 according to the present embodiment is provided with a convex portion 31h that protrudes from the inner side surface of the arm portion 31b toward the other arm portion 31c (F portion).

The front end portion of the convex portion 31h of the outer case 31 has an annular shape when viewed in plan.
2. Internal Configuration of Battery Pack The internal configuration of the battery pack according to the present embodiment will be described with reference to FIG.
As shown in FIG. 8, the battery pack 2 according to the present embodiment includes a core pack 30. The core pack 30 includes a unit cell 35 having a flat rectangular appearance, a PTC element 36, a circuit board 37, a board holder 40, lead plates 38 and 39, an insulating sheet 41, and the like.

Similar to the unit cell 15 according to the first embodiment, the unit cell 35 has a bottomed rectangular tube-shaped outer can 35a and a sealing plate 35b that seals the opening, and a part of the sealing plate 35b is used. Is provided with a negative electrode terminal 35c. The PTC element 36 is disposed on the sealing plate 35b with the insulating sheet 41 interposed therebetween.
In the battery pack 2 according to the present embodiment, the substrate holder 40 does not have an L-shaped appearance, but has a strip shape. The lead plates 38 and 39 are bent in an L shape.

The arm portion 31c of the U-shaped outer case 31 is provided on the outer surface side of the bottom wall of the outer can 35a in the unit cell 35 in the Y-axis direction, similarly to the arm portion 11c of the outer case 11 according to the first embodiment. A plurality of strip-like ribs 31e are provided. In addition, the convex part 31h is provided in the arm part 31b on the opposite side as above-mentioned (refer FIG. 7).
Also in the battery pack 2, the exterior label 32 is adhered to cover the outer periphery of the unit cell 35 and the like so as to cover the outer periphery of the main body 31 a of the exterior case 31 on the left front side in the Y-axis direction. Yes.

3. Attachment of the exterior case 31 to the core pack 30 The attachment form of the exterior case 31 to the core pack 30 is demonstrated using FIG. FIG. 9 is a schematic cross-sectional view showing a portion of the unit cell 35 where the sealing plate 35b is joined and a part of the arm portion 31b of the outer case 31 disposed so as to cover the sealing plate 35b.
As shown in FIG. 9, in the unit cell 35, there is a step between the main surface of the sealing plate 35b and the opening edge 35d of the outer can 35a. This is because, as shown in a portion surrounded by a two-dot chain line is because the outer edge portion 35b ₁ of the sealing plate 35b is up along the opening edge 35d of the outer can 35a, the outer can 35a and the sealing plate 35b bonding is done by the contact portion between the tip portion 35b ₂ of the outer edge portion 35b ₁ of the distal end portion 35d ₁ and the sealing plate 35b of the opening edge 35d of the outer can 35a is laser welded (welding point P _W ). This configuration is the same as in the first embodiment.

In the battery pack 2 according to the present embodiment, the substrate holder 40 is not disposed on the sealing plate 35b. On the sealing plate 35b, the arm portion 31b of the outer case 31 is disposed, and the tip portion of the convex portion 31h is in contact with the sealing plate 35b. The outer edge 31g of the outer case 31, those for both the front end portion 31g ₁ is a distal end portion 35b ₂ of the outer edge portion 35b ₁ of the distal end portion 35d ₁ and the sealing plate 35b of the opening edge 35d of the outer can 35a It touches.

The arm portion 31b of the outer case 31, at the point where the convex portion 31h is formed, and the inner side wall are closely contact with the outer sidewall 31h ₁ and the outer edge portion 35b ₁ of the sealing plate 35b of the protrusion 31h.
4). In the battery pack 2 according to the embodiment of the superiority embodiment, the arm portion 31b of the outer case 31 is provided projecting portions 31h, the tip portion 31h ₂ of the convex portion 31h of the outer case 31 on the main surface of the sealing plate 35b It is in contact. For this reason, when an impact force is applied to the outer case 31 from the outside, the force is not locally transmitted to the joint portion between the outer can 35a and the sealing plate 35b, but also on the main surface of the sealing plate 35b. Distributed.

Also, the outer edge 31g of the outer case 31, the front end portion 31g ₁ is to both of the front end portion 35b ₂ of the outer edge portion 35b ₁ of the distal end portion 35d ₁ and the sealing plate 35b of the opening edge 35d of the outer can 35a Therefore, the force (shearing force) applied to the joint _PW between the outer can 35a and the sealing plate 35b by the force transmitted to the portion can be reduced. Therefore, it is possible to avoid a situation in which the outer can 35a and the sealing plate 35b are disconnected from each other due to an impact force from the outside.

Further, with the above configuration, deformation of the exterior case 31 when the exterior label 32 is wound is reliably suppressed.
Further, in the battery pack 2 according to this embodiment, since the side wall outer surface 31h ₁ of the projecting portion 31h of the outer case 31 is tightly contact with the inner sidewall of the outer edge portion 35b1 of the sealing plate 35b, the outer label 32 When winding, it is suppressed that the exterior case 31 produces position shift or the exterior case 31 deform | transforms.

Further, in the battery pack according to the present embodiment, the tip portion of the convex portion 31h of the outer case 31 has an annular shape in a plan view, so that the workability is higher than in the case of using other shapes. . That is, it is possible to improve the resin flow when using a resin as a material. Therefore, the yield in manufacturing can be improved.
[Other matters]
In the first embodiment and the second embodiment, the battery pack including one unit cell is adopted as an example in the configuration. However, the above-described configuration is also applied to the battery pack including two or more unit cells. Can be adopted. For example, even when the unit cells are stacked in two stages in the Z-axis direction of FIG. 2 and one substrate holder and an exterior case are attached to these unit cells, the characteristic configurations of the substrate holder and the exterior case are also described. By adopting, the same effect can be obtained.

The type of the unit cell is not particularly mentioned in the first embodiment and the second embodiment, but for example, a non-aqueous secondary battery such as a lithium ion battery, a nickel cadmium battery, a nickel hydrogen battery, or the like. An alkaline secondary battery or the like can be applied.
Further, as shown in FIG. 2 and the like, in the first and second embodiments, a plurality of streak ribs 11e and 31e are provided on the inner side surfaces of the arm portions 11c and 31c in the exterior cases 11 and 31. However, when the rigidity can be sufficiently increased by providing a single streak rib, a single streak rib may be provided. Furthermore, it can also be set as the structure which does not provide a streak-like rib.

  In the first embodiment, as shown in FIG. 3, the rib 20d of the substrate holder 20 has a streak shape extending in the longitudinal direction, but the shape of the rib formed on the substrate holder is not limited to this. Absent. For example, the same effect can be obtained by providing a plurality of cylindrical ribs. Further, one columnar rib may be provided for each of both sides on the outer side in the width direction.

  In the first embodiment and the second embodiment, the PTC element 16 is connected to the negative electrode terminal 15c of the unit cell 15 as an example of the heat sensitive element. However, other than the PTC element, for example, NTC (Negative Temperature). It is also possible to connect a Coefficient element or a thermal fuse. In addition, it is not always necessary to connect a thermosensitive element such as a PTC element to the negative electrode terminal of the unit cell, and conversely, a configuration in which it is connected to the positive electrode terminal (including the case of an outer can) of the unit cell is also conceivable.

  Further, in Embodiment 2 described above, the convex portion 31h having a circular ring shape is provided from the inner side surface of the arm portion 31b of the outer case 31. However, the shape of the convex portion is limited to this. Is not to be done. For example, it can be a convex portion having a rectangular or circular tip shape in plan view, or a plurality of ribs. Further, the number of convex portions formed is not necessarily limited to one, and a plurality of convex portions may be provided.

Further, the convex portion provided on the inner side surface of the arm portion of the outer case can be provided at a location that does not interfere with the rib in the substrate holder. In this case, the movement of the exterior case can be regulated (position regulation) when the exterior label is wound by causing the convex portion to contact the inner side wall of the outer edge portion of the sealing plate in the unit cell. .
Moreover, in the said Embodiment 1 and the said Embodiment 2, although the structure by which the exterior labels 12 and 32 were affixed on the battery packs 1 and 2 was made into an example, about an exterior label, it is not necessarily an essential structure. For example, if the unit cell, the circuit board, the PTC element, and the like are covered with an exterior case, the exterior label can be omitted.

  In the first and second embodiments, the circuit boards 17 and 37 are arranged with the board holders 20 and 40 inserted into the outer cans 15a and 35a of the unit cells 15 and 35. The substrate holder is not an essential configuration. That is, it is also possible to adopt a configuration in which the circuit board is disposed to face the outer can of the unit cell without interposing a board holder therebetween. In this case, as in the second embodiment, if a convex portion is provided from the inner main surface of the outer case and its tip is in contact with the main surface of the sealing plate, Even when an impact force is applied from the outside, the force is distributed and transmitted not only to the joint between the outer can and the sealing plate, but also to the main surface of the sealing plate via the convex portion. Damage to the joint with can be reduced.

  Furthermore, in Embodiment 1 described above, the rib 20d of the substrate holder 20 and the outer edge 11g of the outer case 11 are in close contact with each other, so that the position of the outer case 11 with respect to the substrate holder 20 is regulated. However, such a configuration is not indispensable when only considering the dispersion of force when an impact force is applied to the outer case 11. In other words, a plurality of force transmission paths may be formed between the outer case 11 and the outer can 15a and the sealing plate 15b in the unit cell 15.

  The present invention has high appearance quality and high impact resistance, and is useful for realizing a battery pack as a power source for mobile devices.

1,2. Battery pack 10,30. Core pack 11,31. Exterior case 12, 32. Exterior label 13. Submergence determination label 14. External terminal 15, 35. Unit cell 16,36. PTC element 17,37. Circuit board 18, 19, 38, 39. Lead plate 20, 40. Substrate holder 41. Insulating sheet

Claims (7)

A unit cell having a bottomed rectangular tube-shaped outer can and a sealing plate for sealing the opening of the outer can;
A circuit board disposed opposite to one side surface of the outer can in the unit cell;
An outer case attached to the unit cell in a state of covering the circuit board;
With
In the unit cell, the sealing plate is joined to the opening edge of the outer can at the outer edge portion thereof,
The outer case is supported at a contact portion with respect to both the outer edge portion of the sealing plate and the opening end edge portion of the outer can, and directly on the main surface portion excluding the outer edge portion of the sealing plate. Alternatively, a battery pack characterized by being indirectly supported. Furthermore, a board holder inserted between the circuit board and one side surface of the outer can in the unit cell,
The battery pack according to claim 1, wherein the outer case is attached to the unit cell so as to cover the substrate holder. In addition, an exterior label that covers the exterior of the exterior case, the substrate holder, the circuit board, and the unit cell in a state in which a part of the outer surface of the exterior case is exposed,
The substrate holder has an L-shape in which a portion interposed between the circuit substrate and one side surface of the outer can in the unit cell and a portion covering the sealing plate in the unit cell are integrally formed. And
In the part covering the sealing plate in the substrate holder, ribs are erected on the both sides outside in the width direction toward the side opposite to the sealing plate,
In a portion corresponding to the portion of the substrate holder where the rib is provided in the outer case, a streak outer edge is erected toward the sealing plate,
The outer case is indirectly supported on the outer main surface of the sealing plate by the tip portion of the rib in the substrate holder contacting the inner main surface of the outer case.
The battery pack according to claim 2, wherein an inner side surface of the outer edge in the outer case and an outer side surface of the rib in the substrate holder are in close contact with each other. The battery pack according to claim 3, wherein the rib in the substrate holder has a streak shape extending in a longitudinal direction of a portion covering the sealing plate. The outer edge portion of the sealing plate rises along the opening edge of the outer can,
The bonding between the sealing plate and the outer can is performed by welding between an end portion of the rising portion of the sealing plate and an opening edge portion of the outer can. Item 5. The battery pack according to any one of Items 1 to 4. The outer case also has a portion covering the outer surface of the bottom wall of the outer can in the unit cell,
The line-shaped rib extended in a longitudinal direction is formed in the part which covers the bottom wall outer surface of the said exterior can in the said exterior case. The any one of Claims 1-5 characterized by the above-mentioned. The battery pack according to Crab. The substrate holder is provided with a locking portion at a portion exposed to the side of a portion inserted between the circuit board and one side surface of the outer can in the unit cell,
A locked portion is provided in a portion corresponding to the locking portion of the substrate holder in the outer case,
One of the locking part and the locked part is a claw part, and the other is a hole part that receives the insertion of the claw part. Battery pack.

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