JP7110626B2 - electrical equipment - Google Patents

Description

The present invention relates to electrical equipment.

2. Description of the Related Art In a power storage device, which is a type of electrical equipment, a plurality of cells are accommodated in a resin housing as an exterior body. These single cells constitute a single cell group arranged in a line, and end plates are arranged at both ends of the single cell group. The unit cell group and end plates, ie, battery elements, are fixed to the housing by bolts as fastening members. Specifically, the end plate is fixed to the housing by bolts inserted through through holes formed in the housing (see Patent Document 1).

When an electrical element is fixed to an exterior by a fastening member inserted through a through-hole formed in the exterior, the through-hole is sealed, that is, the leakage of gas and liquid between the inside and outside of the exterior is blocked. It is necessary to ensure the reliability. Various fastening structures that can be applied to ensure such tightness are known (see Patent Documents 2 to 4).

JP 2017-059510 Actual Kaihei 5-50136 JP 2012-251583 A Japanese Patent Application Laid-Open No. 2005-73407

However, in the conventional fastening structures including those disclosed in Patent Documents 2 to 4, it is not possible to ensure the hermeticity of the housing of the electrical equipment and to simplify the fastening structure.

The present invention provides an electrical device having a fastening structure for fixing electrical elements housed inside an exterior body to the exterior body. The challenge is to achieve both.

One aspect of the present invention includes an exterior body, an electrical element housed in the exterior body, and a fastening structure for fixing the electrical element to the exterior body, wherein the fastening structure is formed in the exterior body. A fastening member for fastening the electric element to the exterior body, comprising a through hole, a first portion inserted into the through hole, and a second portion adjacent to the portion of the exterior body in which the through hole is formed. and a portion of the exterior body formed with the through hole and the second portion, which are made of resin and protrude from one toward the other, surround the through hole, and surround the exterior body and the second portion. and a protrusion with an asymmetric cross-section that is deformed in a state of pressure contact between and.

According to this aspect, the projection is provided so as to surround the through-hole on one of the portion of the exterior body where the through-hole is formed and the second portion, which is made of resin. By deforming the projections in a press-contact state, airtightness, that is, the ability to block leakage of gas and liquid between the inside and the outside of the exterior body via the through-hole is ensured. Therefore, it is not necessary to use a separate part for ensuring the tightness, such as an O-ring or a sealing member, and the tightness can be secured with a simplified configuration.

The cross-sectional shape of the projection before deformation is an asymmetric triangular shape. According to this aspect, by deforming the protrusion having a triangular cross section, the portion surrounding the through hole and formed with the through hole and the second portion of the exterior body are made of resin. A region is formed in which one is strongly pressed against the other with a small area. As a result, the tightness is improved.

The projection includes a first projection and a second projection, and the second projection is provided closer to the through hole than the first projection. When the projection is arranged outside the exterior body, the first projection provided so as to surround the through-hole is deformed to block leakage of gas and liquid from the exterior to the interior of the exterior body. Further, the deformation of the second projection provided closer to the through hole than the first projection blocks leakage of gas and liquid from the inside of the exterior body to the outside. When the projection is arranged inside the exterior body, the first projection provided so as to surround the through hole is deformed to block leakage of gas and liquid from the inside of the exterior body to the outside. In addition, the deformation of the second protrusion provided inside the first protrusion blocks leakage of gas and liquid from the outside to the inside of the exterior body. In this way, since the protrusion includes the first protrusion and the second protrusion, both gas and liquid leakage from the inside of the exterior body to the outside and gas and liquid leakage from the exterior to the interior of the exterior body can be prevented. can be blocked effectively.

The cross-sectional shape of the first projection before deformation includes a first side and a second side positioned closer to the through hole than the first side, and the length of the second side is the length of the first side. Longer than length. According to this aspect, the first projection is deformed while being compressed so as to fall on the side opposite to the through hole. Therefore, when the protrusion is arranged outside the package, the pressure of gas or liquid directed from the outside to the inside of the package acts to bring the first protrusions into closer contact with each other. Further, when the projection is arranged inside the exterior body, the pressure of the gas or liquid directed from the inside of the exterior body to the outside acts to bring the first projections into closer contact with each other. As a result, leakage of gas and liquid between the outside and the inside of the exterior body can be blocked more effectively.

The cross-sectional shape of the second projection before deformation includes a third side and the fourth side located on the side opposite to the through hole with respect to the third side, and the length of the fourth side is is longer than the length of the third side. According to this aspect, the second projection is compressed and deformed so as to fall toward the through hole. Therefore, when the protrusion is arranged outside the package, the pressure of the gas or liquid directed from the inside to the outside of the package acts to bring the second protrusions into closer contact with each other. Further, when the projection is arranged inside the exterior body, the pressure of gas or liquid directed from the outside to the inside of the exterior body acts to bring the second projections into closer contact with each other. As a result, leakage of gas and liquid between the inside and outside of the exterior can be blocked more effectively.

The projection is arranged outside the exterior body. Here, when the projection is formed inside the exterior body, the projection abuts on the electrical element to be fixed and does not abut on the fastening member. On the other hand, when the protrusion is formed inside the exterior body as in this aspect, the protrusion abuts on the second portion of the fastening member and is firmly brought into close contact with the second portion, so that loosening of the fastening member can be suppressed. Therefore, it is effective for fixing electric elements.

In the electric device of the present invention, the protrusions provided to surround the through-hole are deformed in a press-contact state, thereby blocking leakage of gas and liquid between the inside and outside of the exterior body through the through-hole. ensured. Therefore, it is possible to ensure hermeticity with a simplified configuration.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing which shows the electrical storage apparatus which concerns on 1st Embodiment of this invention. FIG. 2 is a partially enlarged sectional view of FIG. 1; FIG. 2B is a partially enlarged cross-sectional view of FIG. 2A; Partially enlarged cross-sectional view showing a state before fastening. 3B is an enlarged cross-sectional view of the protrusion of FIG. 3A; FIG. FIG. 4 is an enlarged cross-sectional view showing a modification of the projection; FIG. 5 is an enlarged cross-sectional view showing another deformed state of the projection; The expanded sectional view which shows the processus|protrusion of 2nd Embodiment. The enlarged sectional view which shows the protrusion of 3rd Embodiment. The enlarged sectional view which shows the protrusion of 4th Embodiment. The enlarged sectional view which shows the protrusion of 5th Embodiment. Sectional drawing which shows the electrical storage apparatus which concerns on 6th Embodiment. FIG. 11 is a partially enlarged sectional view of FIG. 10; FIG. 11B is a partially enlarged cross-sectional view of FIG. 11A; Sectional drawing which shows the conventional fastening structure for ensuring airtightness. Sectional drawing which shows other conventional fastening structures for ensuring airtightness.

Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 shows a power storage device 10, which is an electrical device according to a first embodiment of the present invention. The power storage device 10 includes a battery module (electric element) 12 made up of a plurality of battery cells 14 (power storage elements) and a busbar unit 20 , which are housed inside an exterior body 22 . In this embodiment, the battery module 12 is fixed to the exterior body 22, and the securing of the hermeticity of the exterior body 22 by these fastening structures and the simplification of the fastening structure are achieved.

In the following description, the lateral direction of the battery cells 14, which is the direction in which the battery cells 14 are arranged, is sometimes referred to as the X direction. Also, the longitudinal direction of the battery cell 14 may be referred to as the Y direction, and the height direction of the battery cell 14 may be referred to as the Z direction. The battery module 12 of this embodiment is a rectangular parallelepiped whose X-direction dimension is longer than its Y-direction dimension.

(Overview of power storage device)
As shown in FIG. 1, the battery module 12 has a plurality of (eight in this embodiment) battery cells 14 arranged in the X direction. Spacers (not shown) are arranged between adjacent battery cells 14 to ensure insulation.

A nonaqueous electrolyte secondary battery such as a lithium ion battery is used as the battery cell 14 . However, various battery cells 14 including a capacitor can be applied other than the lithium ion battery. Each battery cell 14 has a metal container, and the container contains an electrode body in which electrode sheets of a positive electrode and a negative electrode are laminated via a separator, current collectors of the positive electrode and the negative electrode, and an electrolytic solution. ing.

The battery cell 14 is prismatic and has a pair of long side surfaces 15 extending along the YZ plane and a pair of short side surfaces 16 extending along the XZ plane. The dimension of the short side 16 in the X direction is shorter than the dimension of the long side 15 in the Y direction. Moreover, the battery cell 14 has a bottom surface 17 and a terminal surface 18 extending along the XY plane. A positive terminal (not shown) is arranged on one end side in the Y direction and a negative terminal (not shown) is arranged on the other end side in the Y direction on the terminal surface 18 located on the upper side in the Z direction.

The busbar unit 20 includes a plurality of busbars and is arranged on the battery module 12 so as to cover the terminal surfaces 18 of all the battery cells 14 . The plurality of bus bars are electrically connected to the positive and negative terminals of predetermined battery cells 14 to form a power supply circuit that supplies power to the plurality of battery cells 14 . For example, a plurality of busbars are attached to and integrated with a resin busbar frame.

The exterior body 22 is made of resin, and includes a main body 23 with one open surface (an upper surface in the Z direction) and a lid 27 closing the opening of the main body 23 . The main body 23 and the lid 27 are fixed liquid-tight and air-tight by welding or the like.

The main body 23 has a rectangular parallelepiped shape whose X-direction dimension is longer than its Y-direction dimension, and has a rectangular bottom wall 24 . A pair of end walls 25 located outside in the arrangement direction of the battery modules 12 are erected on both ends of the bottom wall 24 in the X direction. On both sides of the bottom wall 24 in the Y direction, a pair of side walls 26 positioned outside in the direction intersecting the arrangement direction of the battery modules 12 are erected.

The lid 27 is provided with a positive external terminal 28 on one end in the X direction and a negative external terminal 29 on the other end in the X direction. The external terminals 28 and 29 protrude upward in the Z direction from the cover 27 and are electrically connected to the busbar unit 20 respectively. The battery module 12 can charge and discharge electricity via the busbar unit 20 and the external terminals 28 and 29 .

The battery module 12 of this embodiment includes a restraining member 32 that restrains the plurality of battery cells 14 , and is fixed (fastened) to the exterior body 22 via the restraining member 32 .

The restraint member 32 is a frame surrounding the outer periphery of the battery module 12, and includes a pair of end plates 33 arranged at both ends in the arrangement direction (X direction) of the battery cells 14, and a Y plate perpendicular to the arrangement direction of the battery cells 14. and a pair of side plates 34 arranged on both sides of the direction. Although these plates 33 and 34 are made of metal in this embodiment, they may be made of a resin harder than the exterior body 22 .

The end plates 33 are plate-shaped and generally cover the outer long side surfaces 15 (end surfaces of the battery modules 12) of the battery cells 14 positioned at both ends in the X direction. The side plate 34 has a strip shape extending in the X direction across the short side surfaces 16 of all the battery cells 14 . Bent fixing portions 35 are provided on both sides of the end plate 33 in the Y direction so as to protrude inward in the X direction. By fixing both ends of the side plates 34 to the fixing portions 35 by bolting or the like, the plurality of battery cells 14 are immovably restrained and integrated.

Referring also to FIG. 2A, a bracket 36 for fixing the battery module 12 to the exterior body 22 is provided at the lower end of the end plate 33 in the Z direction. The bracket 36 is bent so as to protrude outward in the X direction.

(Overview of fastening structure)
As shown in FIG. 2A , the fastening structure for fixing the battery module 12 to the exterior body 22 includes through holes 39 formed in the exterior body 22 , bolts 45 for fastening the battery module 12 to the exterior body 22 , and the exterior body 22 . and a projection 51 deformed between the bolt 45.

The through holes 39 are holes having a larger diameter than the shaft portion 46 of the bolt 45 , and are provided in the recesses 38 formed at the four corners of the bottom wall 24 of the main body 23 . The recess 38 is provided by recessing the bottom wall 24 upward in the Z direction so as to be positioned below the bracket 36 of the end plate 33, and a through hole 39 is formed in the end wall 38a in the Z direction. . The depth of the recess 38 in the Z direction is set so that the head 47 of the bolt 45 does not protrude downward.

Bracket 36 of restraining member 32 is positioned over recess 38 . The bracket 36 is provided with a through portion 41 corresponding to the through hole 39 , and a nut (fastening receiving portion) 42 to which a bolt 45 is fastened is arranged in the through portion 41 . A nut 42 has a threaded hole 43 with an internal thread (see FIG. 3A) and is fixed to the bracket 36 in this embodiment.

The bolt 45 is made of metal and is a fastening member that fastens the battery module 12 including the restraint member 32 to the exterior body 22 . The bolt 45 includes a shaft portion 46 provided with a male thread and a head portion 47 having a regular hexagonal shape when viewed from the axial direction of the shaft portion 46 . The shaft portion 46 is a first portion that is inserted through the through hole 39 of the exterior body 22 . The head 47 is the second portion adjacent to the portion in which the through hole 39 is formed. In this embodiment, the bolt 45 is attached from the outside of the exterior body 22 so that the head 47 is positioned outside the exterior body 22 . On the shaft portion 46 side of the head portion 47, a flange portion (seat surface portion) 48 is formed that protrudes radially outward about the axis of the shaft portion 46 and is pressed around the through hole 39 in the recess portion 38. .

The projection 51 is provided in the recess 38 in which the through hole 39 is formed and the head 47 of the bolt 45, which is easily plastically deformed by relative pressure contact therebetween. That is, the protrusion 51 of this embodiment is provided on the resin-made exterior body 22 . The protrusion 51 is formed in an annular shape surrounding the through hole 39 and protrudes from the recess 38 toward the head 47 (outside of the exterior body 22).

In this embodiment, an annular recess 50 is provided around the through hole 39 in the recess 38 and is recessed away from the head portion 47 . is provided. The protrusions 51A and 51B protrude outward (downward in the Z direction) from the opening of the recess 50 . The diameter of the first protrusion 51A is smaller than the diameter of the flange portion 48 of the bolt 45 . The diameter of the second protrusion 51B is smaller than the diameter of the first protrusion 51A. In other words, the second projection 51B is located on the through hole 39 side located inside the first projection 51A in the radial direction of the recess 38 .

As shown most clearly in FIG. 2B, in the assembled state of power storage device 10, protrusions 51A and 51B are deformed in a press-contact state between recess 38 and head 47. As shown in FIG. Referring to FIGS. 3A and 3B, the cross-sectional shape of the protrusions 51A and 51B before deformation (before assembly) is triangular. The cross-sectional shapes of the projections 51A and 51B before and after deformation are asymmetric with respect to reference lines L1 and L2 passing through the centers of the projections 51A and 51B in the radial direction and parallel to the center line of the through hole 39. be.

As shown most clearly in FIG. 3B, the cross-sectional shape of the first projection 51A before deformation is a right-angled triangular shape with right-angled corners on the radially outer side. In other words, the first protrusion 51A is located radially outward and extends along the reference line L1, and the second side (diagonal side) 52b is located closer to the through hole 39 than the first side 52a. Prepare. The length of the second side 52b is longer than the length of the first side 52a.

The cross-sectional shape of the second protrusion 51B before deformation is a right-angled triangular shape in which the radially inner corner is a right angle. That is, the second protrusion 51B is located radially inside the second protrusion 51A, and extends along the reference line L2. and four sides (hypotenuses) 52d. The length of the fourth side 52d is longer than the length of the third side 52c.

Here, the projections 51A and 51B having a triangular cross-section are not limited to geometrically meaning triangles in which the first side 52a and the second side 52b, and the third side 52c and the fourth side 52d intersect at an acute angle. , which also includes triangles in a practical sense. Specifically, as shown in FIG. 4, sides 52e may be chamfered between the first side 52a and the second side 52b and between the third side 52c and the fourth side 52d. In this case, the dimension S1 of the side 52e is less than or equal to the dimension S2 of the sides 52a and 52c. Also, between the first side 52a and the second side 52b and between the third side 52c and the fourth side 52d, round chamfering may be performed instead of corner chamfering. Shapes such as these are also included in the triangular shape of the present invention.

2A and 3A, a metal collar 54 interposed between nut 42 and head 47 is positioned within throughbore 39 . The outer diameter of the collar 54 is approximately the same as the inner diameter of the through hole 39 , and the inner diameter of the collar 54 is larger than the outer diameter of the shaft portion 46 . The overall length of the collar 54 in the axial direction (Z direction) is substantially equal to the dimension from the lower end face of the recess 38 to the lower end face of the nut 42 . The collar 54 may be insert-molded when the main body 23 is manufactured, or may be press-fitted into the through hole 39 after molding.

(Assembly work of power storage device)
When assembling the power storage device 10 , a plurality of battery cells 14 are arranged in the X direction, and the outer periphery of the battery cell 14 group is bound by the binding member 32 . After that, the busbar unit 20 is arranged on the battery module 12 and the restrained battery module 12 is arranged inside the exterior body 23 . Note that the busbar unit 20 may be arranged after the battery modules 12 are arranged inside the main body 23 .

Next, the battery module 12 (restraint member 32 ) is fixed to the main body 23 with bolts 45 . As shown in FIG. 3A , at the time of fastening, the shaft portion 46 of the bolt 45 is passed through the through hole 39 (collar 54 ) from the outside to the inside of the bottom wall 24 and the bolt 45 is tightened to the nut 42 . As a result, the flange portion 48 comes into contact with the tips of the protrusions 51A and 51B projecting from the recess 50, and the protrusions 51A and 51B are deformed. At this time, the first protrusion 51A is compressed and crushed so as to fall on the side opposite to the through hole 39 by setting the dimensions of the sides 52a and 52b. Also, the second projection 51B is compressed and crushed so as to fall toward the through hole 39 by setting the dimensions of the sides 52c and 52d.

Bolt 45 is tightened against nut 42 until head 47 of bolt 45 and nut 42 abut the end of collar 54 . That is, since the metal collar 54 is interposed between the bolt 45 and the nut 42 , stronger fastening is possible, and loosening of the fastening due to vibration or the like during use of the power storage device 10 can be effectively prevented.

When the battery module 12 is fixed to the main body 23, the busbar unit 20 and the external terminals 28 and 29 of the lid 27 are electrically connected, and then the lid 27 is fixed to the main body 23 by heat welding.

In this power storage device 10, the projections 51A and 51B of the exterior body 22 are deformed in a press-contact state, so that the tightness of the fastening structure portion, that is, between the inside and the outside of the exterior body 22 via the through-hole 39, It is possible to ensure the isolation of gas and liquid leakage. Therefore, it is not necessary to use a separate part for ensuring the tightness, such as an O-ring or a sealing member, and the tightness can be secured with a simplified configuration.

Further, as shown in FIG. 2B, the protrusions 51A and 51B having a triangular cross section are crushed, thereby obtaining an elastic repulsive force due to the resin. This repulsive force forms a narrow area surrounding the through-hole 39 and firmly pressed against the head 47 of the bolt 45 . As a result, the tightness is improved. In particular, in this embodiment, since the first projection 51A and the second projection 51A are provided, leakage of gas and liquid from the inside of the exterior body 22 to the outside and leakage of gas and liquid from the outside of the exterior body 22 to the inside can be effectively blocked.

Specifically, as shown by the dashed line in FIG. 2B, the pressure of the gas or liquid directed from the outside to the inside of the exterior body 22 acts in a direction to raise the first projection 51A, so that an elastic repulsive force due to the resin is applied. increases, and the first projection 51A comes into closer contact with the head 47 more firmly. In addition, since the pressure of the gas or liquid directed from the inside to the outside of the exterior body 22 acts in a direction to raise the second projections 51B, the elastic repulsive force of the resin increases, and the second projections 51B are attached to the head portion 47. Closer and tighter. As a result, the first projection 51A blocks the leakage of gas and liquid from the outside to the inside of the exterior body 22, and the second projection 51B blocks the leakage of gas and liquid from the inside of the exterior body 22 to the outside. be.

Moreover, in this embodiment, the protrusions 51A and 51B are formed outside the exterior body 22, which is effective in fixing the battery module 12. FIG. That is, when the projections 51A and 51B are formed inside the exterior body 22 , the projections 51A and 51B abut against the battery module 12 (end plate 33 ) and do not abut against the bolt 45 . On the other hand, when the protrusions 51A and 51B are formed outside the exterior body 22 , the protrusions 51A and 51B abut on the head 47 of the bolt 45 . Therefore, since the protrusions 51A and 51B are firmly brought into close contact with the bolt 45, loosening of the bolt 45 can be suppressed.

(Other deformed states of protrusions)
As shown in FIG. 5, the protrusions 51A and 51B may be deformed away from each other so as to fall radially outward and inward of the recess 38 without being crushed. Even in this case, the projections 51A and 51B are pressed against the head 47 because of the elastic repulsive force of the resin. In consideration of such deformation, it is preferable to adjust the protrusion amount and formation position so that the protrusions 51A and 51B do not protrude from the recess 50 in the deformed state.

When deformed in this manner, the space between the protrusions 51A and 51B becomes a state close to vacuum like a suction cup. In this case, due to the atmospheric pressure from the outside, force always acts in the direction in which the protrusions 51A and 51B are raised. Therefore, the elastic repulsive force of the resin is increased, and the projections 51A and 51B are strongly brought into close contact with the head portion 47. As shown in FIG. Further, the pressure of the gas or liquid directed from the outside to the inside of the exterior body 22 brings the first projection 51A into closer contact with the head 47, and the pressure of the gas or liquid directed from the inside to the outside of the exterior body 22 causes the head 47 to come into closer contact with the head. The second projection 51B is brought into closer contact with the portion 47 more firmly. As a result, the first projection 51A blocks the leakage of gas and liquid from the outside to the inside of the exterior body 22, and the second projection 51B blocks the leakage of gas and liquid from the inside of the exterior body 22 to the outside. be.

(Second embodiment)
FIG. 6 shows protrusions 51A and 51B formed on the exterior body 22 of the power storage device of the second embodiment. The second embodiment is different from the first embodiment in that projections 51A and 51B are provided so as to protrude from the end face of the end wall 38a of the recess 38 without forming a recess in the end wall 38a.

(Third embodiment)
FIG. 7 shows projections 51 formed on the exterior body 22 of the power storage device of the third embodiment. The third embodiment differs from the first embodiment in that a third protrusion 51C is provided between the first protrusion 51A and the second protrusion 51B. The cross-sectional shape of the third projection 51C is an isosceles triangle shape in which the dimension of the side located on the side opposite to the through hole is the same as the dimension of the side located on the side of the through hole.

(Fourth embodiment)
FIG. 8 shows protrusions 51A and 51B formed on the exterior body 22 of the power storage device of the fourth embodiment. The fourth embodiment differs from the first embodiment in that the inclination angles of the first side 52a of the first protrusion 51A and the third side 52c of the second protrusion 51B are changed. Specifically, the first side 52a of the first protrusion 51A is provided so that the tip thereof is inclined in a direction toward the through hole. The third side 52c of the second projection 51B is provided so that the tip thereof is inclined away from the through hole. The length relationship between the first side 52a and the second side 52b of the first protrusion 51A, and between the third side 52c and the fourth side 52d of the second protrusion 51B is the same as in the first embodiment.

(Fifth embodiment)
FIG. 9 shows protrusions 51A and 51B formed on the exterior body 22 of the power storage device of the fifth embodiment. The fifth embodiment differs from the first embodiment in that the first side 52a of the first protrusion 51A and the third side 52c of the second protrusion 51B are inclined in the opposite direction to the fourth embodiment. . That is, the first side 52a of the first protrusion 51A is provided so that the tip thereof is inclined in a direction away from the through hole. The third side 52c of the second projection 51B is provided so that the tip thereof is inclined in a direction approaching the through hole. The length relationship between the first side 52a and the second side 52b of the first protrusion 51A, and between the third side 52c and the fourth side 52d of the second protrusion 51B is the same as in the first embodiment.

As described above, the protrusions 51A and 51B may be configured as in the second embodiment shown in FIG. 6 to the fifth embodiment shown in FIG. be able to. Also, the projections 51A and 51B of the second embodiment of FIG. 6 to the fifth embodiment of FIG. 9 may be provided with chamfered sides 52e as in the modification of FIG.

(Sixth embodiment)
FIG. 10 shows a power storage device 10 of the sixth embodiment. In this sixth embodiment, the overall height in the Z direction of the recesses 38 formed in the exterior body 22 is increased, and the battery modules 12 (end plates 33) are fastened to the body 23 with bolts 45 near the opening of the body 23. It is different from the first embodiment in this point.

As shown in FIGS. 11A and 11B, the projections 51A and 51B are provided on the upper surface side of the end wall 38a of the recess 38 and deform between the recess 38 and the head 47 of the bolt 45 via the end plate 33. It is The protrusions 51A and 51B may be formed in the same manner as in the modification of FIG. 4 and the second embodiment of FIG. 6 to the fifth embodiment of FIG.

In the sixth embodiment, since the projections 51A and 51B do not come into close contact with the bolt 45, the effect of suppressing loosening of the bolt 45 is reduced. and liquid leak-tightness can be ensured in the same way.

Specifically, as shown by the dashed line in FIG. 11B, the pressure of gas or liquid directed from the inside to the outside of the exterior body 22 is directed to raise the first projections 51A so as to bring the first projections 51A into closer contact with each other. works. Further, the pressure of the gas or liquid directed from the outside to the inside of the exterior body 22 acts in a direction to raise the second projections 51B so as to bring the second projections 51B into closer contact with each other. As a result, the first projection 51A blocks the leakage of gas and liquid from the inside of the exterior body 22 to the outside, and the second projection 51B blocks the leakage of gas and liquid from the outside to the inside of the exterior body 22. be. 5, even if the projections 51A and 51B are not crushed and are deformed so as to fall radially outward and inward of the recess 38, the inside and outside of the exterior body 22 will be separated from each other. It is possible to ensure the isolation of gas and liquid leakage.

(Comparative example)
12 and 13 show conventional fastening structures using special hermetic bolts 60A and 60B. The airtight bolt 60A of FIG. 12 has a head portion 62 (flange portion 63) provided with a recess 64 positioned on the outer circumference of the shaft portion 61, and an O-ring 65 arranged in the recess 64. As shown in FIG. The airtight bolt 60B shown in FIG. 13 has a configuration in which an annular packing portion 66 is provided integrally with the head portion 62 (flange portion 63) so as to protrude in the same direction as the shaft portion 61. As shown in FIG.

The O-rings 65 and the annular packing portions 66 of these airtight bolts 60A and 60B correspond to only one of the pressure of gas or liquid directed from the inside to the outside and the pressure of gas or liquid directed to the inside from the outside. not However, in the power storage device 10, pressure fluctuations in both directions, such as an increase in internal pressure due to an abnormality in the battery cell 14 and an increase in external pressure due to an increase in the outside temperature or submersion in water, etc., can occur.

In the case of the airtight bolt 60A fitted with the O-ring 65, the airtightness can be ensured only between the flange portion 63 and the collar 54. Therefore, in order to ensure airtightness, the collar 54 needs to be insert-molded into the exterior body 22 , which increases the manufacturing cost of the power storage device 10 .

In the case of the airtight bolt 60B provided with the annular packing portion 66, the annular packing portion 66 is pressed against the exterior body 22 (end wall 38a of the recess 38) due to the difference in strength and hardness between the annular packing portion 66 and the exterior body 22 (end wall 38a of the recess 38). The airtightness cannot be sufficiently ensured due to insufficient compression. Therefore, in order to ensure airtightness, it is necessary to insert-mold the collar 54 into the exterior body 22 and additionally perform special processing on the airtight bolt 60B, which increases the manufacturing cost of the power storage device 10.

On the other hand, in the power storage device 10 of the present invention, the projections 51A and 51B provided on the exterior body 22, which is likely to be plastically deformed, are crushed, so that the gas and liquid flow between the inside and outside of the exterior body 22 is suppressed. It is possible to ensure the blocking performance of the leakage of Therefore, the airtightness can be ensured with a simplified configuration without using expensive airtight bolts 60A and 60B.

In addition, the present invention is not limited to the configuration of the above embodiment, and various modifications are possible.

For example, the main body 23 of the exterior body 22 may be made of metal, the bolt (fastening member) 45 may be made of resin, and the projection 51 may be provided on the bolt 45 . The bolt 45 may be configured without the flange portion 48 . The shaft portion (first portion) 46 that constitutes the fastening member may be provided integrally with the bracket 36 of the end plate 33 .

The battery cell 14 that constitutes the electric element may be of a winding type in which a band-shaped electrode sheet and a separator are wound, or may be of a lamination type in which a plurality of rectangular electrode sheets and separators are laminated. good. Moreover, the battery cell 14 is not limited to a prismatic battery in which an electrode body is housed in a container, and may be a laminate type battery in which a laminated electrode body is sealed with a laminate film.

A fastening structure including a through-hole formed in the exterior body, a fastening member for fastening an electric element to the exterior body, and a projection deformed in a state of pressure contact between the exterior body and the fastening member is not limited to power storage device 10. , an exterior body, and an electric element housed in the exterior body.

10... Power storage device (electrical equipment)
12... Battery module (electrical element)
DESCRIPTION OF SYMBOLS 14... Battery cell 15... Long side surface 16... Short side surface 17... Bottom surface 18... Terminal surface 20... Busbar unit 22... Exterior body 23... Main body 24... Bottom wall 25... End wall 26... Side wall 27... Cover body 28... Positive electrode external terminal DESCRIPTION OF SYMBOLS 29... Negative electrode external terminal 32... Restraint member 33... End plate 34... Side plate 35... Fixing part 36... Bracket 38... Recessed part 38a... End wall 39... Through hole 41... Through part 42... Nut (fastening receiving part)
43... screw hole 45... bolt (fastening member)
46 ... Axle (first part)
47 ... head (second part)
48... Flange part 50... Recess 51... Protrusion 51A... First protrusion 51B... Second protrusion 51C... Third protrusion 52a... First side 52b... Second side 52c... Third side 52d... Fourth side 52e... Chamfered side 54... Collar 60A, 60B... Airtight bolt 61... Shaft part 62... Head part 63... Flange part 64... Recessed part 65... O-ring 66... Packing part

Claims (4)

an exterior body;
an electrical element housed in the exterior body;
a fastening structure for fixing the electrical element to the exterior body,
The fastening structure is
a through hole formed in the exterior body;
a fastening member for fastening the electrical element to the exterior body, the fastening member comprising a first portion inserted through the through hole and a second portion adjacent to the portion of the exterior body in which the through hole is formed;
Between the portion in which the through-hole is formed and the second portion of the exterior body, one of which is made of resin and protrudes toward the other, surrounds the through-hole, and connects the exterior body and the second portion. and a first projection with an asymmetric cross-section deformed in a press-contact state between ,
The cross-sectional shape of the first projection before deformation includes a first side and a second side positioned closer to the through hole than the first side, and the length of the second side is the length of the first side. longer than length
the second side is in contact with the other;
electrical equipment. The electric device according to claim 1 , further comprising a second projection provided closer to said through hole than said first projection. The cross-sectional shape of the second projection before deformation is
a third side;
a fourth side located on the side opposite to the through hole with respect to the third side,
The electric device according to claim 2 , wherein the length of the fourth side is longer than the length of the third side. The electric device according to any one of claims 1 to 3 , wherein said first projection is arranged outside said exterior body.

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