JP2017195118A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack capable of suppressing sound resonance.SOLUTION: A battery pack 1 comprises: a battery module 3; a housing 2 for housing the battery module 3; and a sound absorption member 5 provided on the housing 2. The housing 2 has: a main body 20 provided with openings A1 and A2; and a tabular lid 30 for closing the openings A1 and A2. The lid 30 has: a fixed part 31 fixed to the main body 20; and extension parts 32 and 33 extending from the fixed part 31 so as to reach a peripheral part R of the openings A1 and A2. In response to a pressure rise inside the housing 2, the extension parts 32 and 33 are deformed so as to be separated from the peripheral part R with the fixed portion 31 as a starting point, thereby opening the openings A1 and A2. The sound absorption member 5 is adhered to inner faces 32a and 33a of the extension parts 32 and 33.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery pack.

  Patent Document 1 discloses a battery pack that includes a plurality of battery cells and a housing that houses the plurality of battery cells. The battery pack casing is provided with a pressure release portion composed of an opening and a sealing plate for sealing the opening. The pressure release part is that the sealing plate is deformed as the internal pressure of the housing rises, so that the gas filled in the housing is discharged to the outside from the opening, and the pressure in the housing rises abnormally. It is preventing.

JP 2011-198570 A

  In the battery pack described above, the sealing plate that functions as a so-called safety valve is formed of a thin plate having low rigidity. For this reason, the sealing plate is more likely to vibrate than other portions of the housing. Therefore, for example, when a battery pack is mounted on a vehicle, sound may be generated due to vibration of the sealing plate.

  The present invention provides a battery pack capable of suppressing the sound of sound.

  A battery pack according to the present invention includes a battery module, a housing that houses the battery module, and a sound absorbing member that is provided in the housing, and the housing closes the main body provided with an opening and the opening. A lid having a plate shape, the lid having a fixed portion fixed to the main body, and an extending portion extending from the fixed portion to the peripheral edge of the opening. Opens the opening by being deformed so as to be separated from the peripheral portion starting from the fixed portion in response to an increase in pressure in the housing, and the sound absorbing member is adhered to the inner surface of the extending portion.

  In this battery pack, the extended portion of the lid that closes the opening of the main body of the housing is deformed so as to be separated from the peripheral portion with the fixed portion as a starting point in response to an increase in pressure in the housing. Is released. That is, the lid functions as a so-called safety valve that prevents the pressure in the housing from rising abnormally. Therefore, the lid body is easier to vibrate than the other part of the housing as described above. On the other hand, in this battery pack, a sound absorbing member is attached to the inner surface of the extending portion. For this reason, the sound of the sound resulting from the vibration of the lid can be suppressed.

  In the battery pack according to the present invention, the inner surface includes a first region facing the peripheral portion, the sound absorbing member is attached to the first region, and the first member is closed in a state where the lid closes the opening. You may be compressed by the area | region and the peripheral part. In this case, the gap between the peripheral edge portion and the first region can be sealed with the sound absorbing member. That is, it is possible to reduce the number of parts by sharing a member for absorbing sound and a member for sealing.

  In the battery pack according to the present invention, the first space and the second cavity are formed in the internal space of the housing, and the inner surface faces the second region facing the first cavity and the second cavity. And the volume of the second cavity is larger than the volume of the first cavity, and the sound absorbing member may be adhered to the third area. In this case, the volume of the second cavity is larger than that of the first cavity, and sound is likely to sound. Since the sound absorbing member is attached to the third region of the inner surface facing the second cavity, the sound reverberation can be efficiently suppressed.

  The sound absorbing member according to the present invention may be adhered to the entire inner surface. In this case, the sound can be further suppressed. Further, as described above, the gap between the peripheral edge portion and the first region can be sealed by the sound absorbing member.

  The sound absorbing member may be made of a foamable material. In this case, the sound of the sound can be effectively suppressed by the air bubbles inside the foamable material.

  ADVANTAGE OF THE INVENTION According to this invention, the battery pack which can suppress the sound of a sound can be provided.

It is a perspective view which shows the battery pack which concerns on embodiment. It is a disassembled perspective view of the battery pack of FIG. It is sectional drawing along the III-III line of FIG. It is a top view which shows the inner surface of the cover body shown by FIG. It is sectional drawing which shows the battery pack which concerns on a modification. It is a top view which shows the cover body by which the sound-absorbing member shown by FIG. 5 was stuck.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are used for the same or equivalent elements, and redundant descriptions are omitted.

  First, the battery pack according to the embodiment will be described with reference to FIGS. FIG. 1 is a perspective view showing the battery pack according to the first embodiment. FIG. 2 is an exploded perspective view of the battery pack of FIG. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a plan view showing an inner surface of the lid shown in FIG.

  As shown in FIGS. 1 to 3, the battery pack 1 includes a housing 2, a plurality of battery modules 3, a connector 4, and a sound absorbing member 5. The battery pack 1 is a device used as a battery for vehicles such as electric vehicles and forklifts. The battery pack 1 is accommodated in a predetermined battery accommodating portion.

  The housing | casing 2 is a box which exhibits a rectangular parallelepiped shape as a whole. The housing 2 accommodates a plurality of battery modules 3 in the internal space S of the housing 2. In the present embodiment, the housing 2 accommodates four battery modules 3. In the internal space S, a first cavity S1 and a second cavity S2 are formed. The first cavity S1 and the second cavity S2 will be described later.

  The housing 2 has a box-shaped main body 20 and a plate-shaped lid body 30. The main body 20 has a substantially rectangular parallelepiped shape as a whole, and includes a bottom wall portion 21, an upper wall portion 22, a first side wall portion 23, a second side wall portion 24, a front wall portion 25, and a rear wall portion 26. Contains. The main body 20 is integrated by welding or fastening by bolts (not shown). The main body 20 is provided with openings A1 and A2. The openings A1 and A2 will be described later.

  The bottom wall portion 21, the upper wall portion 22, the first side wall portion 23, the second side wall portion 24, the front wall portion 25 and the rear wall portion 26 are formed of a general steel material such as SS400 and SPHC, for example. The bottom wall portion 21 is formed of, for example, a rectangular plate material having a thickness of 50 mm. The upper wall portion 22 is formed of, for example, a plate material having a thickness of 10 mm. The 1st side wall part 23 and the 2nd side wall part 24 are formed with the board | plate material whose thickness is 25 mm, for example. The front wall portion 25 and the rear wall portion 26 are formed of, for example, a plate material having a thickness of 5 mm.

  The first side wall part 23, the second side wall part 24, the front wall part 25, and the rear wall part 26 are erected along four sides forming the periphery of the bottom wall part 21. The first side wall part 23 and the second side wall part 24 face each other. The first side wall portion 23 and the second side wall portion 24 are provided with a plurality of screw holes H1 for fixing the battery module 3 to the first side wall portion 23 and the second side wall portion 24 with bolts B1. The front wall portion 25 and the rear wall portion 26 face each other.

  The upper wall portion 22 is connected to the ends of the first side wall portion 23, the second side wall portion 24, the front wall portion 25, and the rear wall portion 26 opposite to the bottom wall portion 21. They are facing each other. The direction in which the first side wall 23 and the second side wall 24 oppose each other is the X direction, the direction in which the front wall 25 and the rear wall 26 oppose each other in the Y direction, and the bottom wall 21 and the upper wall 22 oppose each other. Hereinafter, the direction will be described as the Z direction.

  The upper wall portion 22 is provided with openings A1 and A2 at the center in the Y direction. The openings A1 and A2 have a rectangular shape with the same shape. The openings A1 and A2 are arranged in parallel in the X direction. The opening A1 is disposed on the first side wall portion 23 side, and the opening A2 is disposed on the second side wall portion 24 side. The upper wall portion 22 has a peripheral edge R that forms the periphery of the openings A1 and A2.

  The peripheral portion R includes portions R1 to R7. The portion R1 is located between the opening A1 and the opening A2, and extends in the Y direction. The portion R1 is provided with a plurality of screw holes H2 arranged in the Y direction for fixing the lid 30 to the portion R1 with bolts B2. The portion R2 faces the portion R1 along the X direction across the opening A1, and extends in the Y direction. The portion R3 faces the portion R1 along the X direction across the opening A2, and extends in the Y direction. The length of the portion R2 in the X direction is equal to the thickness (thickness) of the first side wall portion 23 in the X direction, and the length of the portion R3 in the X direction is the thickness of the second side wall portion 24 in the X direction. It is equivalent to thickness (thickness).

  The portion R4 is located on the front wall portion 25 side of the opening A1 and extends in the X direction. The portion R5 is located on the rear wall portion 26 side of the opening A1, and extends in the X direction. The portion R5 faces the portion R4 along the Y direction across the opening A1. The portion R6 is located on the front wall 25 side of the opening A2, and extends in the X direction. The portion R7 is located on the rear wall portion 26 side of the opening A2, and extends in the X direction. The portion R7 faces the portion R6 along the Y direction across the opening A2.

  The lid body 30 is formed of a rectangular plate material. The thickness and rigidity of the lid body 30 are smaller than the thickness and rigidity of each part of the main body 20. The lid 30 is made of a plate material having a thickness of 5 mm, for example. The lid 30 is disposed on the upper wall portion 22 and closes the openings A1 and A2. The lid 30 faces the peripheral edge R along the Z direction. The lid 30 has an inner surface 30a and an outer surface 30b. The inner surface 30 a is a surface that is disposed on the side of the openings A <b> 1 and A <b> 2 and forms the inner surface of the housing 2. The outer surface 30 b is a surface that is disposed on the side opposite to the inner surface 30 a and forms the outer surface of the housing 2. The lid 30 includes a fixed portion 31 and extending portions 32 and 33.

  The fixing part 31 is a part fixed to the main body 20. The fixing portion 31 extends in the Y direction at the center of the lid 30 in the X direction. The fixed portion 31 is provided with a plurality of through holes H3 arranged in the Y direction. The plurality of through holes H3 are provided at positions overlapping the plurality of screw holes H2 when viewed from the Z direction. The fixing portion 31 faces the portion R1 and is fixed to the portion R1 with a bolt B2. The bolt B2 is inserted through the through hole H3 and a through hole H4 described later, and is fastened to the screw hole H2.

  The extending part 32 is a part that extends from the fixed part 31 to the parts R2, R4, and R5 of the peripheral edge R and closes the opening A1. The extending part 32 is not fixed to the main body 20. For this reason, the extension part 32 is deformed (for example, elastically deformed (hereinafter the same)) so as to be separated from the parts R2, R4, and R5 starting from the fixed part 31 as the pressure in the housing 2 increases. Thus, the opening A1 is opened. Opening the opening A1 means communicating the internal space S and the outside of the housing 2 through the opening A1.

  The extending part 33 is a part that extends from the fixed part 31 to the parts R3, R6, and R7 of the peripheral edge R and closes the opening A2. The extending part 33 is not fixed to the main body 20. For this reason, the extension part 33 opens the opening A2 by being deformed so as to be separated from the parts R3, R6 and R7 with the fixing part 31 as a starting point in response to an increase in the pressure in the housing 2.

  That is, the lid body 30 functions as a so-called safety valve by opening the openings A1 and A2 by deformation of the extending portions 32 and 33, and prevents the pressure in the housing 2 from exceeding a specified pressure. The specified pressure is set lower than the pressure at which the casing 2 is damaged when the pressure in the casing 2 increases. The lid 30 is formed of a thin plate having lower rigidity than the other parts of the housing 2 as described above in order to ensure the ease of deformation of the extending portions 32 and 33.

The extending portion 32 has an inner surface 32a that forms part of the inner surface 30a. The inner surface 32a includes a region (first region) 32a _1, a region (second region) 32a _2, a. The region 32a ₁ is a region that forms the periphery of the inner surface 30a, and faces the portions R2, R4, and R5 in a state where the lid 30 closes the opening A1. The region 32a ₂ is a region other than the region 32a _{1 on the} inner surface 32a, and faces the first cavity S1 when the lid 30 closes the opening A1.

The extending portion 33 has an inner surface 33a that forms a part of the inner surface 30a. The inner surface 33a includes a region (first region) 33a _1, a region (third region) 33a _2, a. The region 33a ₁ is a region that forms the periphery of the inner surface 30a, and faces the portions R3, R6, and R7 in a state where the lid 30 closes the opening A2. The region 33a ₂ is a region other than the region 33a _{1 on the} inner surface 33a, and faces the second cavity S2 in a state where the lid 30 closes the opening A2.

The first cavity S1 and the second cavity S2 are spaces in which devices such as the battery module 3 and members such as the sound absorbing member 5 are not arranged in the internal space S. Specifically, the first cavity S1 is a space sandwiched between the regions 32a ₂ and the battery module 3 along the Z direction. The second cavity S2 is a space sandwiched between the regions 33a ₂ and the battery module 3 along the Z direction. Here, the volume of the first cavity S1 is equal to the volume of the second cavity S2.

  The battery module 3 includes a plurality of battery cells (not shown), a pair of end plates 11, and a pair of brackets 12. The battery cell is a storage battery such as a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery, or an electric double layer capacitor. The plurality of battery cells are electrically connected to each other and arranged in the Y direction. The pair of end plates 11 are arranged on both sides in the Y direction of the plurality of battery cells arranged in this way. The pair of end plates 11 fixes and integrates a plurality of battery cells.

  The bracket 12 is a member for fixing and attaching a plurality of battery cells to the housing 2. The bracket 12 is attached to the end plate 11 on both sides in the Y direction of the plurality of battery cells. The bracket 12 is attached to the end plate 11 with a bolt (not shown), for example. The bracket 12 is provided with a plurality of through holes H5 for fixing the battery module 3 to the first side wall portion 23 and the second side wall portion 24.

  The through hole H5 overlaps with the screw hole H1 when viewed from the X direction. The battery module 3 is fixed to the first side wall portion 23 and the second side wall portion 24 by a bolt B1 inserted through the through hole H5 and fastened to the screw hole H1. In the present embodiment, two battery modules 3 are fixed to each of the first side wall part 23 and the second side wall part 24.

  The connector 4 is a part that connects the battery pack 1 and an external device. For example, the connector 4 is disposed on the upper wall portion 22 side and the second side wall portion 24 side of the front wall portion 25.

The sound absorbing member 5 is provided on the lid 30. Here, the sound absorbing member 5 has the same shape as the lid 30 when viewed from the direction intersecting the inner surface 30a (here, the Z direction), and is adhered to the entire inner surface 30a. That is, it can be said that the sound absorbing member 5 is adhered to the entire inner surfaces 32a and 33a included in the inner surface 30a. In addition, it can be said that the sound absorbing member 5 is attached to the entire regions 32a ₁ and 33a ₁ which are part of the inner surfaces 32a and 33a. The thickness of the sound absorbing member 5 (distance in the Z direction) is uniform in the XY plane, for example, 7 mm.

  The sound absorbing member 5 is made of, for example, a foam material. The foamable material contains air bubbles generated by foaming and can absorb sound by the air bubbles. Examples of the foamable material include polyurethane sponge and EPDM (ethylene / propylene / diene rubber) sponge.

The sound absorbing member 5 is provided with a plurality of through holes H4 arranged in the Y direction. The plurality of through holes H4 are provided at positions overlapping the plurality of screw holes H2 and the plurality of through holes H3 when viewed from the Z direction. A bolt B2 fastened to the screw hole H2 is inserted through the through hole H3 and the through hole H4. The fixing portion 31 is fixed to the portion R1 with a bolt B2. In a state in which the lid 30 closes the openings A1 and A2, the sound absorbing member 5 has the areas 32a ₁ and 33a ₁ pressed against the peripheral edge R by the elastic force of the lid 30 and the areas 32a ₁ and 33a ₁ Compressed by the peripheral edge R.

Specifically, the sound absorbing member 5 is compressed by the region 32a ₁ and the partial R2, R4 and R5 in a state where the lid body 30 closes the aperture A1. Also, the sound absorbing member 5 is compressed by the region 33a ₁ and the partial R3, R6 and R7 in a state where the lid body 30 closes the aperture A2. The compression rate of the sound absorbing member 5 in these states is, for example, 70 to 80%. Thus, the sound absorbing member 5 is compressed in the region _32a 1, 33a ₁ and the peripheral portion R, it closes the gap between the regions _32a 1, 33a ₁ and the peripheral portion R, functions as a sealing member .

  As described above, in the battery pack 1, the extending portions 32 and 33 of the lid 30 that closes the openings A <b> 1 and A <b> 2 of the main body 20 of the housing 2 are fixed according to an increase in the pressure in the housing 2. The openings A1 and A2 are opened by being deformed so as to be separated from the peripheral edge R of the openings A1 and A2 with the portion 31 as a starting point. That is, the lid 30 functions as a so-called safety valve that prevents the pressure in the housing 2 from rising abnormally. The lid 30 is formed of a thin plate having lower rigidity than the other parts of the housing 2 in order to ensure the ease of deformation of the extending portions 32 and 33. For this reason, the lid 30 is more likely to vibrate than other parts of the housing 2.

  Therefore, in the battery pack 1, the sound absorbing member 5 is attached to the entire inner surfaces 32a and 33a of the extending portions 32 and 33. The sound absorbing member 5 absorbs the vibration of the extending portions 32 and 33 and suppresses the sound of the sound. The sound absorbing member 5 further absorbs reverberant sound in the housing 2. As a result, the sound of the battery pack 1, mainly the sound of the sound due to the vibration of the extending portions 32 and 33, is suppressed.

Moreover, since the sound absorbing member 5 is made of a foam material, the sound of the sound is effectively suppressed by the air bubbles inside the sound absorbing member 5. Furthermore, the sound absorbing member 5 is also attached to the regions 32a ₁ and 33a ₁ facing the peripheral edge R of the openings A1 and A2, and the regions 32a ₁ and 33a in a state where the lid 30 closes the openings A1 and A2. ₁ and the peripheral edge R are compressed. This makes it possible to seal the sound-absorbing element 5 the gap between the peripheral portion R and the region _32a 1, 33a _1. That is, it is possible to reduce the number of parts by sharing a member for absorbing sound and a member for sealing.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It deform | transforms in the range which does not change the summary described in each claim, or applied to another thing. There may be.

  For example, the sound absorbing member 5 may be attached to the inner surfaces 32a and 33a of the extending portions 32 and 33, and is not necessarily attached to the entire inner surface 30a. FIG. 5 is a cross-sectional view showing a battery pack according to a modification. FIG. 6 is a plan view showing a lid body to which the sound absorbing member shown in FIG. 5 is attached. As shown in FIGS. 4 to 6, the battery pack 1 </ b> A according to the modification mainly includes the point that the sound absorbing member 5 is not attached to the entire inner surface 30 a, and the housing 2 includes three battery modules 3. The battery pack 1 is different from the battery pack 1 (see FIG. 3) in that the first cavity S1 and the second cavity S2 have different volumes.

  In the battery pack 1A, the housing 2 houses three battery modules 3. Among them, two battery modules 3 are fixed to the first side wall portion 23, and one battery module 3 is fixed to the second side wall portion 24. The battery module 3 fixed to the second side wall portion 24 is fixed to the bottom wall portion 21 side. For this reason, the volume of the second cavity S2 is larger than that of the first cavity S1, the sound is more likely to sound than the first cavity S1, and the reverberation is large.

Therefore, in the battery pack 1A, the sound absorbing member 5 is attached to the region 32a ₁ and the entire inner surface 33a, that is, the regions 33a ₁ and 33a ₂ . Thus, since the sound absorbing member 5 is adhered to the region 33a ₂ facing the second cavity S2, the sound of sound can be efficiently suppressed. Moreover, since the sound absorbing member 5 is not attached to the region 32a ₂ facing the first cavity S1, the cost for the sound absorbing member 5 can be reduced.

Further, in the battery pack 1 or 1A, the sound absorbing member 5 may be provided only in the regions 32a ₂ and 33a ₂ , for example. In this case, a normal seal member can be separately provided between the regions 32a ₁ and 33a ₁ and the peripheral edge R. Specifically, it is possible to provide a seal member between provided with a seal member between the regions 32a ₁ and the partial R2, R4 and R5, the region 33a ₁ and the partial R3, R6 and R7.

In the battery packs 1 and 1A, the thickness of the sound absorbing member 5 may be different. For example, the thickness of the sound absorbing member 5 provided in the regions 32a ₂ and 33a ₂ may be thicker than the thickness of the sound absorbing member 5 provided in the regions 32a ₁ and 33a ₁ . The thickness of the sound absorbing member 5 provided in the regions 32a ₂ and 33a ₂ is set between the regions 32a ₂ and 33a ₂ and the battery module 3 so that the first cavity S1 and the second cavity S2 are not formed in the internal space S. May be equivalent to the distance in the Z direction. Thereby, the reverberation sound in the housing | casing 2 becomes still easier to be absorbed.

  Further, the battery pack 1, 1A only needs to have at least one opening A1, A2. Further, the battery pack 1, 1 </ b> A only needs to include at least one extending portion 32, 33.

DESCRIPTION OF SYMBOLS 1,1A ... Battery pack, 2 ... Case, 3 ... Battery module, 5 ... Sound absorption member, 20 ... Main body, 30 ... Lid body, 31 ... Fixed part, 32, 33 ... Extension part, 32a, 33a ... Inner surface, 32a ₁ , 33a ₁ ... area (first area), 32a ₂ ... area (second area), 33a ₂ ... area (third area), A1, A2 ... opening, R ... peripheral edge, S ... internal space, S1 ... first cavity, S2 ... second cavity.

Claims (5)

A battery module;
A housing for housing the battery module;
A sound absorbing member provided in the housing,
The housing has a main body provided with an opening, and a plate-like lid that closes the opening,
The lid body has a fixing portion fixed to the main body, and an extending portion extending from the fixing portion to reach a peripheral edge portion of the opening,
The extending portion opens the opening by being deformed so as to be separated from the peripheral portion with the fixed portion as a starting point in response to an increase in pressure in the housing,
The sound absorbing member is attached to the inner surface of the extending part,
Battery pack. The inner surface includes a first region facing the peripheral edge,
The sound absorbing member is attached to the first region, and is compressed by the first region and the peripheral portion in a state where the lid closes the opening.
The battery pack according to claim 1. A first cavity and a second cavity are formed in the internal space of the housing,
The inner surface includes a second region facing the first cavity and a third region facing the second cavity;
The volume of the second cavity is larger than the volume of the first cavity,
The sound absorbing member is attached to the third region,
The battery pack according to claim 1 or 2. The sound absorbing member is attached to the entire inner surface,
The battery pack according to any one of claims 1 to 3. The sound absorbing member is made of a foamable material,
The battery pack according to any one of claims 1 to 4.

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