JP6912277B2 - Battery pack - Google Patents

Description

The present invention relates to a battery pack.

Conventionally, as a battery pack, a first case as a first pack member in which a battery cell as a battery is arranged and a second case as a second pack member assembled in the first case with the battery cell sandwiched between them. Cases, and those provided with a locking portion provided in the first case and the second case and holding the assembled state of the first case and the second case (for example,) are known. See Patent Document 1).

In this battery pack, the first case and the second case are made of resin, and the locking portion is provided in the receiving hole as an engaged portion provided in the first case and in the second case. It has a hooking claw as an engaging portion, and by engaging the hooking claw with the receiving hole, the assembled state of the first case and the second case is maintained.

However, in a battery pack as in Patent Document 1, since the hooking claw as the locking portion and the receiving hole are made of resin, the mechanical strength of the locking portion is low, and the locking portion is subjected to impact, vibration, or the like. There was a risk of disengagement.

Therefore, in order to improve the impact resistance and vibration resistance of the locking portion, one end of the non-flexible metal member can be insert-molded into a pack member made of resin, and the other end of the metal member exposed from the pack member can be bent. It is conceivable to provide an engaged portion in which the engaging portion is engaged.

In a battery pack in which a metal member is insert-molded inside a pack member made of such a resin, a connecting portion as an embedded portion of a P-pole bus bar as a metal member is embedded in the mold resin to serve as an engaged portion. It is known that the external connection terminal portion is provided on the exposed portion exposed from the mold resin (see, for example, Patent Document 2).

By applying the insert molding of the metal member to the resin of Patent Document 2 to the locking portion of Patent Document 1, the mechanical strength of the engaged portion in the locking portion can be increased, and the resistance of the locking portion can be increased. Impact resistance and vibration resistance can be improved.

Japanese Unexamined Patent Publication No. 2008-27616 Japanese Unexamined Patent Publication No. 2013-21324

However, in a battery pack as in Patent Document 2, since the embedded portion embedded in the resin of the metal member has a corner portion, the fluidity of the resin during insert molding is poor, and the strength of the pack member is lowered. If the resin and the metal member expand or contract due to a temperature change or the like, there is a risk of damage.

Therefore, an object of the present invention is to provide a battery pack capable of improving the strength of the pack member.

The invention according to claim 1 is a first pack member in which a battery is arranged, a second pack member assembled to the first pack member with the battery interposed therebetween, the first pack member and the second pack member. The battery pack is provided with a locking portion for holding the assembled state of the first pack member and the second pack member, and the first pack member and the second pack member are The locking portion is made of resin, and the locking portion is provided at one of the first pack member and the second pack member, which is continuous with one member so as to be flexible, and the other is provided with the engagement portion. It has an engaged portion to which the joint portion is engaged, and the engaged portion is a deflection embedded in the other of the first pack member and the second pack member via an embedded portion. It is provided in an exposed portion of an impossible metal member, and the corner portion of the embedded portion is formed in an R shape in which the end portion of the resin in which the corner portion is located is not the starting point of the weld line. ..

In this battery pack, since the corners of the embedded portion are formed in an R shape, the fluidity of the resin during insert molding can be improved, the strength of the pack member can be improved, and the pack member and the metal member can be changed due to temperature changes or the like. It is possible to suppress damage due to expansion and contraction that occur in and.

Therefore, in such a battery pack, the strength of the pack member can be improved.

The invention according to claim 2 is the battery pack according to claim 1, wherein the embedded portion is provided with the engaged portion in a symmetrical shape.

In this battery pack, since the engaged portion is provided symmetrically in the embedded portion, it is assumed that the exposed portion side of the metal member is arranged on the inner side of the pack member when the metal member is inserted into the resin. Also, the engaged portion on the embedded portion side of the pack member can be exposed from the pack member, and the engaged portion can be engaged with the engaging portion.

Therefore, it is not necessary to pay attention to the directionality of the metal member at the time of insert molding, and the productivity can be improved.

The invention according to claim 3 is the battery pack according to claim 1 or 2, wherein the engaged portion is formed of a hole penetrating the metal member.

In this battery pack, since the engaged portion is formed by a hole penetrating the metal member, resin can flow into the engaged portion during insert molding, and the metal member is stably held in the pack member. can do.

According to the present invention, it is possible to provide a battery pack capable of improving the strength of the pack member.

It is an exploded perspective view of the battery pack which concerns on embodiment of this invention. It is an enlarged perspective view of the main part which made a part of the 1st pack member of the battery pack which concerns on embodiment of this invention a cross section. It is an enlarged perspective view of the main part of the 2nd pack member of the battery pack which concerns on embodiment of this invention. FIG. 5 is an enlarged perspective view of a main part having a cross section of a part of the battery pack according to the embodiment of the present invention. It is an enlarged sectional view of the main part of the battery pack which concerns on embodiment of this invention. It is a front view of the metal member of the battery pack which concerns on embodiment of this invention. It is an enlarged perspective view of the main part of the 2nd pack member of the battery pack which concerns on embodiment of this invention. (A) is a perspective view in which a metal member whose corners are not R-shaped is insert-molded into a resin. (B) is a perspective view in which a metal member having R-shaped corners is insert-molded into a resin. (A) is a perspective view when a metal member whose corners are not R-shaped is insert-molded into a resin. (B) is a perspective view when a metal member having R-shaped corners is insert-molded into a resin. (A) is a figure which shows the flow of the resin with respect to the metal member which does not have the corner part R shape. (B) is a figure which shows the flow of the resin with respect to the metal member which made the corner part R-shaped. (A) is a figure which shows the temperature change of the resin with respect to the ambient temperature when the metal member which does not have the corner part R shape is insert-molded into the resin. (B) is a figure which shows the temperature change of a resin with respect to the ambient temperature at the time of insert molding a metal member having an R-shaped corner part into a resin.

The battery pack according to the embodiment of the present invention will be described with reference to FIGS. 1 to 11.

The battery pack 1 according to the present embodiment includes a first pack member 5 on which a battery is arranged, a second pack member 7 assembled to the first pack member 5 with a battery interposed therebetween, and a first pack member 5 and a first pack member 5. The two-pack member 7 is provided with a locking portion 9 for holding the assembled state of the first pack member 5 and the second pack member 7.

Further, the first pack member 5 and the second pack member 7 are made of resin, and the locking portion 9 is a engaging portion 11 provided so as to be bendable by one member continuous with the first pack member 5, and a second. It has an engaged portion 13 provided on the two-pack member 7 and to which the engaging portion 11 is engaged.

Further, the engaged portion 13 is provided in the exposed portion 19 of the non-flexible metal member 15 embedded in the second pack member 7 via the embedded portion 17.

The corner portion 21 of the buried portion 17 is formed in an R shape.

Further, the embedded portion 17 is provided with the engaged portion 13 in a symmetrical shape.

Further, the engaged portion 13 is formed of a hole penetrating the metal member 15.

As shown in FIGS. 1 to 7, the battery (not shown) is composed of a rechargeable and dischargeable secondary battery, and the electrode element is housed in a rectangular parallelepiped main body and electrically connected to the electrode element. The positive and negative pole connection portions are arranged on the same surface of the main body.

In this battery, a plurality of (here, four) batteries are arranged in parallel in the width direction, and a surface opposite to the connection portion is arranged on the first pack member 5.

The first pack member 5 is made of an insulating material such as synthetic resin, is formed in a bottomed housing shape, and is a first set in which a housing portion 25 for accommodating a plurality of batteries and a second pack member 7 are assembled. It is provided with an attachment portion 27.

The accommodating portion 25 is formed at the bottom of the first pack member 5 in a rectangular shape similar to the outer shape of the battery, and a plurality of (here, four) are partitioned by a partition wall as in the arrangement shape of the plurality of batteries. Have been placed.

The first assembling portion 27 is located on the outer periphery of the accommodating portion 25, and is provided in a plurality of concave shapes (six in this case) so as to open the upper surface of the outer peripheral wall 29 erected from the bottom of the first pack member 5. ing.

The second assembly portion 33 of the second pack member 7 is inserted into the first assembly portion 27, and the second pack member 7 is assembled to the first pack member 5.

The second pack member 7 is made of an insulating material such as synthetic resin, and is assembled to the first pack member 5 so as to sandwich the plurality of batteries from the connection portion side of the plurality of batteries, and is attached to the connection portion side of the plurality of batteries. It includes an arrangement portion 31 to be arranged and a second assembly portion 33 to be assembled to the first assembly portion 27 of the first pack member 5.

The arrangement portion 31 is arranged on the connection portion side of a plurality of batteries in a state where the first pack member 5 and the second pack member 7 are assembled, and is divided into a plurality of portions corresponding to the connection portions to be connected. There is.

The arrangement unit 31 includes a plurality of bus bars (not shown) for connecting a plurality of battery connection portions, electric wires (not shown) connected to sensors for detecting the battery status and the temperature of the bus bars, and a battery pack. An external connection portion (not shown) for electrically connecting 1 and an externally arranged device is provided.

A plurality of second assembly portions 33 are formed in a prismatic shape from the surface of the arrangement portion 31 facing the first pack member 5 at positions corresponding to the first assembly portion 27 on the outer circumference of the second pack member 7 (here, 6). One) It is erected.

A metal member 15 to be inserted into the first assembly portion 27 is exposed at the tip of the second assembly portion 33, and an engaged portion 13 is formed on the metal member 15 to form the first assembly. The locking portion 9 is formed by the engaging portion 11 formed in the attachment portion 27.

The locking portion 9 is engaged with the engaging portion 11 provided in the first assembling portion 27 of the first pack member 5 and the engaging portion provided at the tip of the second assembling portion 33 of the second pack member 7. It is composed of a part 13.

The engaging portion 11 is formed flexibly by one member continuous with the outer peripheral wall 29 in the first assembling portion 27 of the first pack member 5, and is projected inside the first assembling portion 27. ..

The engaging portion 11 is a metal member provided at the tip of the second assembling portion 33 that is inserted into the first assembling portion 27 when the first pack member 5 and the second pack member 7 are assembled. When the metal member 15 is completely inserted into the first assembly portion 27, it is reconstructed and engaged with the engaged portion 13 provided on the metal member 15.

The metal member 15 is formed in a plate shape so as to have a rigidity such that it does not bend when it comes into contact with the engaging portion 11, and can be inserted into the first assembling portion 27 from the tip of the second assembling portion 33. It is formed longer than the resin portion of the second assembly portion 33 so as to have a long length, and includes an embedded portion 17 and an exposed portion 19.

The embedded portion 17 is provided on one end side of the metal member 15, and is insert-molded into the second pack member 7 so as to be embedded in the resin portion of the second assembly portion 33 of the second pack member 7. It is provided integrally with the member 7.

The exposed portion 19 is provided on the other end side of the metal member 15, and in a state where the embedded portion 17 is embedded in the second assembly portion 33, the exposed portion 19 is external to the second pack member 7 from the tip of the second assembly portion 33. Be exposed to.

An engaged portion 13 is provided on the exposed portion 19 exposed from the tip of the second assembly portion 33.

The engaged portion 13 is composed of a hole penetrating the metal member 15 in the plate thickness direction, and the depth of the hole of the engaged portion 13, that is, the plate thickness of the metal member 15 is the protrusion height of the engaging portion 11. It is set to be equivalent.

The engaging portion 11 is inserted and engaged with the engaged portion 13 in a state where the first pack member 5 and the second pack member 7 are assembled, and the first pack member 5 and the second pack are engaged. The assembled state with the member 7 is maintained.

By providing the engaged portion 13 of the locking portion 9 on the metal member 15 in this way, the engagement between the engaging portion 11 and the engaged portion 13 becomes the engagement between the resin and the metal, and the locking portion The mechanical strength in 9 can be significantly increased.

Here, the embedded portion 17 of the metal member 15 is insert-molded inside the second pack member 7.

Since the expansion coefficient of the second pack member 7 and the metal member 15 made of resin is different, if the second pack member 7 and the metal member 15 expand or contract due to a temperature change in the external environment or the like, the second pack member 7 and the metal member 15 have different expansion coefficients. Stress is generated within 7.

When stress is generated in such a second pack member 7, the stress may cause cracks or cracks in the second pack member 7, but the starting point is likely to be generated from the weld portion of the second pack member 7. ..

Therefore, when the embedded portion 17 insert-molded in the second pack member 7 has a corner portion, the fluidity of the resin when molding the second pack member 7 is poor, the weld line becomes large, and the second pack member 7 becomes large. There was a risk that the strength of the member 7 would decrease.

Therefore, in the embedded portion 17 of the metal member 15, the corner portion 21 is formed in an R shape.

By forming the corner portion 21 of the embedded portion 17 into an R shape in this way, it is possible to improve the fluidity of the resin when the metal member 15 is insert-molded into the second pack member 7, and the weld line is reduced. Therefore, the strength of the second pack member 7 can be improved.

Therefore, even if the second pack member 7 and the metal member 15 expand or contract due to a temperature change in the external environment or the like, the weld line that is the starting point of the damage is small, so that the second pack member 7 is damaged. Can be significantly suppressed.

Here, as shown in FIGS. 8 to 11, in the insert molding of a metal member 15a in which the corner portion 21a of the buried portion 17a is not in the R shape and a metal member 15 in which the corner portion 21 of the buried portion 17 is in the R shape. The flow analysis of the resin 35 was performed.

The metal member 15a and the metal member 15 are arranged in the mold 37, and are insert-molded by flowing the resin 35 from the gate 39 into the mold 37. The shade of color of the resin 35 in FIG. 11 indicates the temperature change of the resin 35 with respect to the ambient temperature, and the light-colored portion indicates the portion where the temperature change is large.

In the metal member 15a whose corners 21a are not R-shaped, as shown in FIG. 10A, when the resin 35 is filled in the mold 37, the outside of the metal member 15a flows in the flow of the resin 35. There is a large difference between the outer resin 35a and the inner resin 35b that flows inside the metal member 15a.

Therefore, in the metal member 15a, as shown in FIG. 11A, a large weld line 41 is generated in the resin 35 after molding, and the temperature change with respect to the ambient temperature of the resin 35 after molding is also large.

In addition, the weld line 41 of the metal member 15a starts from the end of the resin 35 where the corner portion 21a is located, and the corner portion 21a is not R-shaped.

Therefore, since the weld line 41 is the starting point for cracks and cracks that occur when stress is generated in the second pack member 7 (resin 35), the metal member 15a in which the large weld line 41 is generated becomes the second pack member 7. It can be seen that cracks and cracks are likely to occur.

On the other hand, in the metal member 15 having the corner portion 21 having an R shape, as shown in FIG. 10B, there is a large difference between the outer resin 35a and the inner resin 35b in the flow of the resin 35 as compared with the metal member 15a. Has not occurred.

Therefore, in the metal member 15, as shown in FIG. 11B, the resin 35 after molding does not have a large weld line 41, and the temperature change of the resin 35 after molding with respect to the ambient temperature is small.

In addition, the weld line 41 of the metal member 15 does not start from the end of the resin 35 where the corner 21 is located, and the corner 21 has an R shape.

Therefore, in the metal member 15, the weld line 41, which is the starting point of cracks and cracks, is small, so that cracks and cracks in the second pack member 7 are less likely to occur, and the strength of the second pack member 7 can be improved. I know I can do it.

As described above, from the result of the flow analysis, it is possible to improve the fluidity of the resin at the time of insert molding and improve the strength of the second pack member 7 by forming the corner portion 21 of the embedded portion 17 into an R shape. Understand.

Here, in the metal member 15, the exposed portion 19 is exposed from the tip of the second assembling portion 33 of the second pack member 7, and the engaged portion 13 is provided on the exposed portion 19, but the metal member 15 Was erroneously placed on the inside side of the second pack member 7 on the exposed portion 19 side of the metal member 15 when the metal member 15 was insert-molded on the second pack member 7.

If nothing is provided on the embedded portion 17 side of the metal member 15, if the exposed portion 19 of the metal member 15 is embedded inside the second pack member 7, the portion that engages with the engaging portion 11 will be formed. It cannot be used as the second pack member 7.

When the directionality of the arrangement of the metal member 15 at the time of insert molding is determined in this way, the work must be performed while paying attention to the directionality of the metal member 15, resulting in a decrease in productivity.

Therefore, in the embedded portion 17 of the metal member 15, the engaged portion 13 is provided in a symmetrical shape with the engaged portion 13 provided in the exposed portion 19.

By providing the engaged portion 13 in the embedded portion 17 in a symmetrical shape in this way, when the metal member 15 is insert-molded into the second pack member 7, the exposed portion 19 side is set to the inner side of the second pack member 7. Even if they are arranged, the embedded portion 17 is exposed from the second pack member 7, and the engaged portion 13 of the embedded portion 17 can be engaged with the engaging portion 11.

Therefore, the directionality of the arrangement of the metal member 15 is lost, and it is not necessary to pay attention to the directionality of the metal member 15 at the time of insert molding, and the productivity can be improved.

In addition, since the engaged portion 13 provided in the exposed portion 19 and the embedded portion 17 is formed of a hole penetrating the metal member 15, resin flows into the engaged portion 13 during insert molding. , The metal member 15 can be stably held inside the second pack member 7.

Since there is no directionality in the arrangement of the metal member 15 and the exposed portion 19 may be embedded inside the second pack member 7, the corner portion 21 of the exposed portion 19 is also formed in an R shape and is exposed. Even when the portion 19 is arranged on the inner side of the second pack member 7, the fluidity of the resin can be improved and the strength of the second pack member 7 can be improved.

In such a battery pack 1, since the corner portion 21 of the embedded portion 17 is formed in an R shape, the fluidity of the resin at the time of insert molding can be improved, the strength of the second pack member 7 can be improved, and the temperature can be improved. Damage due to expansion or contraction that occurs between the second pack member 7 and the metal member 15 due to changes or the like can be suppressed.

Therefore, in such a battery pack 1, the strength of the second pack member 7 can be improved.

Further, since the engaged portion 13 is provided in the embedded portion 17 in a symmetrical shape, the exposed portion 19 side of the metal member 15 is placed inside the second pack member 7 when the metal member 15 is inserted into the resin. Even if it is arranged on the side, the engaged portion 13 on the embedded portion 17 side of the second pack member 7 is exposed from the second pack member 7, and the engaged portion 13 is engaged with the engaging portion 11. Can be done.

Therefore, it is not necessary to pay attention to the directionality of the metal member 15 at the time of insert molding, and the productivity can be improved.

Further, since the engaged portion 13 is formed of a hole penetrating the metal member 15, the resin can flow into the engaged portion 13 at the time of insert molding, and the metal member 15 is brought into the second pack member 7. Can be held stably.

In the battery pack according to the embodiment of the present invention, the number of batteries housed inside is four, but the present invention is not limited to this, and four or more or four or less batteries may be housed inside. good.

Further, the engaging portion is provided on the first pack member and the engaged portion is provided on the second pack member, but the present invention is not limited to this, and the engaging portion is provided on the second pack member and the engaged portion is provided. May be provided on the first pack member.

1 ... Battery pack 5 ... 1st pack member 7 ... 2nd pack member 9 ... Locking part 11 ... Engaging part 13 ... Engaged part 15 ... Metal member 17 ... Embedded part 19 ... Exposed part 21 ... Corner part

Claims (3)

The first pack member on which the battery is arranged, the second pack member assembled to the first pack member with the battery interposed therebetween, and the first pack member provided on the first pack member and the second pack member. A battery pack including a locking portion for holding the assembled state of the member and the second pack member.
The first pack member and the second pack member are made of resin.
The locking portion engages with an engaging portion provided so as to be bendable by one continuous member of the first pack member and the second pack member, and the engaging portion provided on the other. It has an engaged part to be fitted and
The engaged portion is provided on an exposed portion of an inflexible metal member embedded in the other of the first pack member and the second pack member via an embedded portion.
The battery pack is characterized in that the corner portion of the embedded portion is formed in an R shape in which the end portion of the resin in which the corner portion is located is not the starting point of the weld line. The battery pack according to claim 1.
A battery pack characterized in that the engaged portion is provided in the embedded portion in a symmetrical shape. The battery pack according to claim 1 or 2.
The battery pack is characterized in that the engaged portion is formed of a hole penetrating the metal member.

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