JP2013258063A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of components of a power storage device.SOLUTION: A power storage device 1 includes: a power storage cell 2 capable of charging and discharging; a housing 3 that is a container having an opening 6H at one end part and houses the power storage cell 2; a conductor lid 3T with which one electrode body of the power storage cell 2 is electrically connected, the conductor lid 3T attached to the opening 6H; a conductor terminal 4 which is electrically connected with the other electrode body of the power storage cell 2 and is led out from the lid 3T to the exterior of the lid 3; and a pressure regulator 40 which is provided at the lid 3T for adjusting an internal pressure of the housing 3; and a resin sealing member 10 which is disposed between the lid 3T and the terminal 4 and is integrally molded with the lid 3T and the terminal 4, the sealing member 10 where at least a part of the pressure regulator 40 is formed.

Description

  The present invention relates to a power storage device that can be charged and discharged.

  As a power storage device that can charge and discharge electricity, an electric double layer capacitor, a secondary battery, and the like are known. For example, Patent Document 1 describes a technique for connecting an external terminal and a negative electrode connection plate connected to a power generation element group by caulking.

JP 2011-233399 A

  Since the technique described in Patent Document 1 uses caulking, a large number of parts are required for a connection portion with an external terminal. An object of the present invention is to reduce the number of parts of a power storage device.

  The present invention relates to a chargeable / dischargeable storage cell having two polar bodies, a container having an opening at one end, a housing for storing the storage cell, and one of the polar bodies being electrically A conductor lid connected to the opening and attached to the opening; a conductor terminal electrically connected to the other polar body and drawn out of the housing from the lid; and provided on the lid A pressure adjusting mechanism that adjusts the pressure inside the housing, and is interposed between the lid and the terminal, and at least a part of the pressure adjusting mechanism is formed so as to be integrated with the lid and the terminal. And a sealing member made of resin molded in (1).

  In this invention, it is preferable that the yield strength of the said terminal is smaller than the yield strength of the said sealing member.

  In the present invention, the recording terminal preferably has a substantially rectangular cross section perpendicular to the drawing direction and has the same size and shape throughout the drawing direction.

  In the present invention, the lid is a plate-shaped member, and the terminal has a flat surface on the inner side of the casing, and the flat surface of the terminal is on the inner side of the casing of the lid. It is preferable to arrange in a plane substantially the same as the surface.

  In this invention, it is preferable that the exterior side of the said housing | casing of the said terminal protrudes from the said sealing member.

  In the present invention, it is preferable that the terminal is a plate-like member and has a protruding portion on the outer peripheral portion.

  In the present invention, it is preferable that the protruding portion has an outer thickness larger than that of the inner side.

  In the present invention, it is preferable that the pressure adjusting mechanism has a gas-liquid separation membrane on the housing side.

  In the present invention, the opening is preferably substantially rectangular in plan view.

  The present invention relates to a chargeable / dischargeable storage cell having two polar bodies, a container having an opening at one end, a housing for storing the storage cell, and one of the polar bodies being electrically A conductor lid connected to the opening and attached to the opening; a conductor terminal electrically connected to the other polar body and drawn out of the housing from the lid; and provided on the lid A pressure adjusting mechanism that adjusts the pressure inside the housing, and is interposed between the lid and the terminal, and at least a part of the pressure adjusting mechanism is formed so as to be integrated with the lid and the terminal. And the terminal has a substantially rectangular cross section perpendicular to the pulling direction, and has the same size and shape throughout the pulling direction. It is smaller than the bonding strength between the sealing member and the terminal. It is a power storage device and butterflies.

  The present invention can reduce the number of parts of a power storage device.

FIG. 1 is a perspective view illustrating the power storage device according to the first embodiment. FIG. 2 is an AA arrow view of FIG. FIG. 3 is a perspective view of the first polar body, the second polar body, and the separator. FIG. 4 is a perspective view illustrating a housing and a storage cell of the power storage device according to the first embodiment. FIG. 5 is an electric circuit diagram of the power storage device according to the first embodiment. FIG. 6 is a plan view of the sealing member and the lid. FIG. 7 is a BB arrow view of FIG. FIG. 8 is a view taken along the line CC of FIG. FIG. 9 is a plan view of the terminal. FIG. 10 is a cross-sectional view of the overhanging portion of the terminal. FIG. 11 is a cross-sectional view of the pressure regulating valve. FIG. 12 is a perspective view including a cross section of the pressure regulating valve. FIG. 13 is a side view of the power storage device according to the second embodiment. FIG. 14 is a perspective view of a housing and a storage cell included in the power storage device according to the second embodiment. FIG. 15 is an electric circuit diagram of the power storage device according to the second embodiment. FIG. 16 is a perspective view illustrating a lid of the power storage device according to the second embodiment. FIG. 17 is a perspective view illustrating a lid of the power storage device according to the second embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a perspective view illustrating the power storage device according to the first embodiment. FIG. 2 is an AA arrow view of FIG. FIG. 3 is a perspective view of the first polar body, the second polar body, and the separator. FIG. 4 is a perspective view illustrating a housing and a storage cell of the power storage device according to the first embodiment. FIG. 5 is an electric circuit diagram of the power storage device according to the first embodiment.

  In the present embodiment, the power storage device 1 is an EDLC (Electric Double Layer Capacitor). However, the power storage device 1 is not limited to EDLC, and may be a secondary battery such as a lithium ion capacitor, an electrolytic capacitor, a nickel metal hydride battery, or a lithium ion battery.

<Outline of power storage device>
As shown in FIG. 1, the power storage device 1 is a device having an overall rectangular parallelepiped shape in which a lid 3 </ b> T is joined to a housing 3. The housing 3 is a container (a container with a bottom) having a side periphery 3S, a bottom 3B provided at one end of the side periphery 3S, and an opening provided at the other end of the side periphery 3S. . As shown in FIG. 2, the housing 3 has a storage chamber 6 inside. The storage chamber 6 is a space surrounded by the side periphery 3S and the bottom 3B of the housing 3. The housing 3, more specifically the storage chamber 6, stores the storage cell 2 shown in FIG. 2. In the housing 3 in which the storage cell 2 is housed, the opening provided at the other end of the side peripheral portion 3S is closed with a lid 3T.

  The lid 3T is a plate-like member having a substantially rectangular shape in a plan view, and the side surfaces of the two largest planes arranged in parallel are connected to each other. In the present embodiment, the lid 3T is a plate-like member having a rectangular shape in plan view, but has four corners that are curved. Note that the four corners do not necessarily have to be formed into a curved surface, and may have a chamfered structure, for example. In this embodiment, the substantially rectangular shape in plan view includes not only a rectangle having four corners but also a portion corresponding to the four corners having a curved surface or a chamfered structure (the same applies hereinafter). .

  From the lid 3T, a conductor terminal 4 electrically connected to the polar body of the electricity storage cell housed in the housing 3 is drawn out of the housing 3 (more specifically, the housing chamber 6). . The terminal 4 is pulled out from the sealing member 10 attached to the lid 3T. The sealing member 10 has an electrolyte solution injection part 11 for injecting an electrolyte solution into the storage chamber 6 of the housing 3 and a part of a pressure regulating valve 40 as a pressure regulating mechanism. The material of the sealing member 10 is resin, and is integrally molded (for example, injection-molded) together with the lid 3T, a part of the pressure regulating valve 40, the electrolyte injection part 11 and the terminal 4. In addition, the sealing member 10 should just have at least one part of the pressure regulation valve 40, and the electrolyte solution injection | pouring part 11 does not necessarily need to have it. Next, the storage cell 2 will be described.

<Structure of storage cell>
The power storage cell 2 shown in FIG. 2 has at least one power storage unit 2U shown in FIG. As shown in FIG. 3, the power storage unit 2U includes two polar bodies, that is, a first polar body 21 provided with an active material layer on the surface and a second polar body provided with an active material layer on the surface. It has a polar body 22 and can be charged and discharged. Both the first polar body 21 and the second polar body 22 are conductors. In the present embodiment, the first polar body 21 and the second polar body 22 are both conductive foils or sheets. The 1st polar body 21 and the 2nd polar body 22 can be manufactured with aluminum or an aluminum alloy, for example. A separator 23 is sandwiched between the first polar body 21 and the second polar body 22. The active material of the first polar body 21 and the active material of the second polar body 22 are opposed to the separator 23.

  The 1st polar body 21 and the 2nd polar body 22 are immersed in electrolyte solution with the active material provided in the separator 23 and each surface. The active material layers provided on the surface of the first polar body 21 and the surface of the second polar body 22 form a first polarizable electrode 24A and a second polarizable electrode 24B, respectively. The first polarizable electrode 24A and the second polarizable electrode 24B are, for example, those obtained by mixing activated carbon with a binder or the like (a conductive auxiliary agent may be further added). It can form by apply | coating to the surface of this.

  In the present embodiment, both the first polar body 21 and the second polar body 22 form an electric double layer capacitor. That is, the first polar body 21, the second polar body 22, and the separator 23 constitute an EDLC. The electricity storage cell 2 has at least one electricity storage unit 2U that is a combination of the first electrode body 21, the second electrode body 22, and the separator 23. In the present embodiment, the electricity storage cell 2 has a plurality of the combinations. Yes. As described above, each of the power storage cells 2 is an EDLC and is a chargeable / dischargeable power storage element. When the power storage device 1 is an EDLC, the first polar body 21 and the second polar body 22 have no polarity.

  The voltage between the first polar body 21 and the second polar body 22 in one power storage unit 2U corresponds to the inter-terminal voltage of the power storage cell 2. The power storage cell 2 may have one power storage unit 2U, or a plurality of power storage units 2U may be stacked via a separator 23 and connected in parallel. In the former case, for example, the first polar body 21 of one power storage unit 2U is electrically connected to the terminal 4 of the power storage device 1, for example. In the latter case, the first polar bodies 21 of the plurality of power storage units 2U are electrically connected to each other, and the second polar bodies 22 of the plurality of power storage units 2U are electrically connected to each other.

  When the power storage cell 2 has a plurality of power storage units 2U, for example, as shown in FIG. 4, a first lead portion 21E of a conductor that is electrically connected to the first pole body 21 of the plurality of power storage units 2U and pulled out. The two are electrically connected by the first connection conductor 25. In addition, the second lead portions 22E of the conductors that are electrically connected and drawn with the second polar bodies 22 of the plurality of power storage units 2U are electrically connected by the second connection conductor 26. The first connection conductor 25 and the second connection conductor 26 are, for example, those in which a good electrical conductor such as copper or aluminum is formed in a sheet shape.

  With such a structure, the first polar bodies 21 of the plurality of power storage units 2U are electrically connected to each other, and the second polar bodies 22 of the plurality of power storage units 2U are electrically connected to each other, A power storage cell 2 having a power storage unit 2U is produced. As illustrated in FIG. 4, the storage cell 2 is stored in the storage unit 6 through the opening 6 </ b> H included in the side periphery 3 </ b> S of the housing 3.

<Structure of lid and housing>
The housing 3 and the lid 3T are structures for partitioning the storage cell 2 from the outside. The lid 3T is electrically connected to one of the first polar body 21 and the second polar body 22 of the storage cell 2 housed in the housing 3 and the other is electrically connected to the terminal 4. For this reason, the lid 3T is at least a conductor. In the present embodiment, the housing 3 is also a conductor, but the housing 3 is not necessarily a conductor. In the present embodiment, the first polar body 21 is electrically connected to the terminal 4 via the first connection conductor 25 shown in FIG. Moreover, the 2nd polar body 22 is electrically connected with the lid | cover 3T through the 2nd connection conductor 26 shown in FIG.

  In the present embodiment, the lid 3T and the housing 3 are, for example, aluminum alloy, but the material of the lid 3T and the housing 3 is not limited to this. The side peripheral part 3S which the housing | casing 3 has is a cylindrical member. A bottom 3B is provided at one end of the side periphery 3S, and an opening 6H is provided at the other end. In the present embodiment, the side peripheral portion 3S and the bottom portion 3B of the housing 3 are integrally molded. However, even if the housing 3 is manufactured by joining both members as separate members by welding means or the like. Good.

  When the bottom 3B and the side periphery 3S of the housing 3 are integrally molded, for example, a processing method that is a kind of cold forging called impact molding can be used. Note that the method of manufacturing the housing 3 is not limited to impact molding. By integrally forming the bottom 3B and the side periphery 3S, the joining of the bottom 3B and the side periphery 3S can be omitted, so that the power storage device 1 can achieve the effects of simplifying the manufacturing process and reducing the number of components. . Further, by integrally molding the bottom 3B and the side periphery 3S by impact molding, it is possible to reduce the possibility that the electrolytic solution sealed in the housing 3 leaks.

  A lid 3T is attached to the opening 6H of the storage portion 6 that opens to the end of the side peripheral portion 3S on the side opposite to the bottom 3B shown in FIG. More specifically, the lid 3T is attached to the end portion (opening side end portion) of the side peripheral portion 3S on the opening 6H side. The lid 3T is joined and fixed to the side periphery 3S of the housing 3 by a joining means such as welding.

  The lid 3 </ b> T has a terminal 4 that is electrically connected to either the first polar body 21 or the second polar body 22 of the storage cell 2 and drawn out of the housing 3. The terminal 4 is a conductor as described above, and is pure aluminum or an aluminum alloy in this embodiment. The material of the terminal 4 is not limited to pure aluminum or aluminum alloy. The terminal 4 passes through the lid 3T from the storage chamber 6 and is drawn out of the lid 3T. As shown in FIGS. 1 and 2, a sealing member 10 is interposed between the terminal 4 and the lid 3T. The sealing member 10 is a member for ensuring electrical insulation between the terminal 4 and the lid 3T that is a conductor. The sealing member 10 seals the storage chamber 6 by sealing the gap between the terminal 4 and the lid 3T. With such a structure, leakage of the electrolyte from the storage chamber 6 is suppressed. For this reason, as described above, a resin is used as the material of the sealing member 10. The resin used as the material of the sealing member 10 is particularly preferably a resin having high electrical insulation and sealing performance.

<Storage cell circuit>
As shown in FIG. 5, in the present embodiment, either one of the first polar body 21 or the second polar body 22 (in this example, the first polar body 21) of the storage cell 2 is electrically connected to the terminal 4. The other (second polar body 22 in this example) is electrically connected to the lid 3T. In the present embodiment, since the lid 3T is a conductor (for example, an aluminum alloy), the electrical conductivity and the thermal conductivity are good. In the power storage device 1, the power storage cell 2 generates heat, but one of the first polar body 21 and the second polar body 22 is connected to the lid 3T having good thermal conductivity. For this reason, the heat generated in the storage cell is transmitted from either the first polar body 21 or the second polar body 22 to the lid 3T and is radiated from the surface of the lid 3T. For this reason, the electrical storage apparatus 1 has the advantage that heat dissipation performance is high. Note that unevenness or fins may be provided on the surface of the lid 3T. If it does in this way, since the surface area of the lid | cover 3T will become large, the thermal storage performance of the electrical storage apparatus 1 will improve further. Next, the sealing member 10 and the terminal 4 will be described.

<Sealing member and terminal>
FIG. 6 is a plan view of the sealing member and the lid. FIG. 7 is a BB arrow view of FIG. FIG. 8 is a view taken along the line CC of FIG. FIG. 9 is a plan view of the terminal. FIG. 10 is a cross-sectional view of the overhanging portion of the terminal. The sealing member 10 is interposed between the conductor lid 3 </ b> T and the conductor terminal 4. As the resin of the sealing member 10, for example, PPS (Poly Phenylene Sulfide) is used, but is not limited thereto. The sealing member 10 is formed with a valve case 41 and a shaft 42 which are a part of the pressure regulating valve 40, and an electrolyte injection part 11. With such a structure, the number of parts can be reduced. The sealing member 10 is integrally molded (for example, injection molding) into the opening 3TH of the lid 3T together with the valve case 41, the shaft 42, the electrolyte solution injection portion 11, and the terminal 4. In the present embodiment, the opening 3TH penetrates through the two largest planes of the lid 3T, which is a plate-like member having a substantially rectangular shape in plan view. As shown in FIG. 6, a gas passage 43 is opened between the valve case 41 and the shaft 42. The gas passage 43 will be described later.

  When the sealing member 10 is molded integrally with the lid 3T together with the terminals 4 and the like, as shown in FIGS. 6 to 8, the peripheral portion 3TE of the opening 3TH of the lid 3T enters the sealing member 10, and both are Combined. With such a structure, strength and sealing performance can be ensured. In this embodiment, since the sealing member 10 is molded integrally with the lid 3T together with the terminals 4 and the like, a member for fixing the terminals 4 to the sealing member 10 and between the sealing member 10 and the terminals 4 are used. Since no seal member or the like is required, the number of parts can be reduced. Further, since the lid 3T, the terminal 4, the valve case 41, and the like are integrally molded with the resin sealing member 10, the operation of attaching the terminal 4 to the lid 3T and the valve case 41 and the electrolyte injection part 11 are attached to the lid 3T. Since the work can be omitted, the power storage device 1 can be easily manufactured.

  The electrolyte injection part 11 has an injection passage 11H that penetrates the sealing member 10 in the thickness direction (drawing direction) of the terminal 4 provided in the sealing member 10. After the lid 3T is attached to the casing 3 and both are joined, the electrolyte is injected into the casing 3, more specifically, into the storage chamber 6 from the injection passage 11H. When the injection of the electrolytic solution is completed, the injection passage 11H is sealed with a resin lid or the like. In the present embodiment, the electrolytic solution is injected into the storage chamber 6 from the electrolytic solution injection unit 11, but the electrolytic solution injection unit 11 is not necessarily used. The pressure regulating valve 40 has a passage that communicates the storage chamber 6 and the outside of the storage chamber 6 and a valve body that opens and closes the passage. Before the valve body is attached, the electrolytic solution is stored in the storage chamber from the passage described above. 6 may be injected. In this way, since the electrolyte solution injection part 11 can be omitted, the structure of the sealing member 10 can be further simplified.

  As shown in FIGS. 7 to 9, the terminal 4 is a plate-like member having a rectangular shape in plan view. The terminal 4 has a terminal body 4B and an overhanging portion 4F. The terminal body 4B has the two largest planes (terminal surfaces) 4t and 4i, and a side portion 4S that connects the two. An external terminal such as a bus bar is electrically connected to the terminal surface 4t on the outer side of the lid 3T, and the first pole body 21 and the like are electrically connected to the terminal surface 4i on the inner side of the lid 3T via the first connection conductor 25 and the like. Connected to. The overhanging portion 4F is a portion protruding from the outer peripheral portion, that is, the side portion 4S. As shown in FIGS. 7 and 8, the protruding portion 4 </ b> F of the terminal 4 enters a part of the sealing member 10 to connect the terminal 4 and the sealing member 10. With such a structure, the terminal 4 and the sealing member 10 are firmly connected and the sealing performance can be secured.

  The terminal 4 has a substantially rectangular cross section perpendicular to the direction in which the casing 3 is drawn from the storage chamber 6 (the direction indicated by the arrow T in FIGS. 7 and 8), and has the same size and shape throughout the entire drawing direction. By doing in this way, the terminal 4 can fully ensure the cross-sectional area which an electric current passes. The power storage device 1 is used as a power storage means of a so-called hybrid construction machine or the like, but a construction machine (for example, a hybrid excavator, a hybrid wheel loader, or the like) passes through the terminal 4 because the frequency of power running and regeneration is large. The integrated value of current increases. For this reason, since the cross-sectional area which the electric current of the terminal 4 passes can be enlarged by making the terminal 4 into the structure mentioned above, the loss of electric power and the heat_generation | fever of the terminal 4 can be suppressed.

  Moreover, since the terminal 4 can increase the cross-sectional area through which the current passes, the area of the terminal surface 4t can also be increased. An external terminal such as a bus bar is electrically connected to the terminal surface 4t. However, since the area of the terminal surface 4t can be increased, the connection area between the terminal surface 4t and the external terminal can be increased. As a result, the connection strength between the two can be increased. In particular, when a power storage device is used in a so-called hybrid construction machine, the power storage device 1 is used in a harsh environment where vibration and impact are large. However, since the power storage device 1 is firmly connected to the terminal surface 4t and an external terminal, both There is also an advantage that the reliability of the connection is improved.

  In the present embodiment, the above-described drawing direction is a direction orthogonal to the terminal surfaces 4 t and 4 i of the terminal 4. An external terminal such as a bus bar is electrically connected to the terminal surface 4t, and the first electrode body 21 and the like of the storage cell 2 are electrically connected to the terminal surface 4i via the first connection conductor 25 and the like. A current flows between the external electrode and the storage cell 2 described above. For this reason, the lead-out direction is a direction in which current flows between the external electrode and the storage cell 2 at the terminal 4.

  As shown in FIG. 10, the overhanging portion 4F increases in thickness (dimension in the direction perpendicular to the terminal surface 4i) as the distance from the side portion 4S of the terminal body 4B increases. For this reason, as for the overhang | projection part 4F, the thickness Lo of the outer side 4FS is larger than the thickness Li of the inner side 4FI. With such a structure, when the overhanging portion 4F is embedded in the sealing member 10, the sealing member 10 is engaged with the overhanging portion 4F, so that the connection strength between the two is further improved. The overhang | projection part 4F can be formed by coining the terminal 4, for example.

  It is preferable that the terminal 4 and the lid 3 </ b> T are subjected to surface treatment in order to improve the connection strength between the terminal 4 and the lid 3 </ b> T and the sealing member 10. Such surface treatment includes, for example, a treatment such as applying a silane coupling agent or the like to the terminal 4 and the lid 3T. By such surface treatment, the connection strength between the terminal 4 and the lid 3T and the sealing member 10 is improved.

  In this embodiment, as shown in FIGS. 7 and 8, the terminal surface 4 i of the terminal 4, that is, the terminal surface 4 i on the storage chamber 6 side of the housing 3 is inside the housing 3 of the lid 3 T, that is, The casing 3 is disposed in substantially the same plane as the surface 3Ti on the storage chamber 6 side, preferably in the same plane. The 2nd polar body 22 of the electrical storage cell 2 is electrically connected to surface 3Ti in the storage chamber 6 side of the lid | cover 3T through the 2nd connection conductor 26 by joining methods, such as ultrasonic pressure connection. In addition, the first electrode body 21 of the storage cell 2 is electrically connected to the terminal surface 4i through the first connection conductor 25 by a joining technique such as ultrasonic pressure connection. For this reason, by arranging the terminal surface 4i and the surface 3Ti of the lid 3T substantially in the same plane, preferably in the same plane, the reference for joining the terminal surface 4i and the first connection conductor 25 and the surface 3Ti of the lid 3T. And the reference for joining the second connection conductor 26 can be made the same. By doing in this way, the positioning operation | work at the time of joining the terminal surface 4i and the 1st connection conductor 25, and the positioning operation | work at the time of joining the surface 3Ti of the lid | cover 3T and the 2nd connection conductor 26 are simplified. Can do.

  In the present embodiment, the outside of the housing 3 of the terminal 4 (the terminal surface 4 t in the present embodiment) protrudes from the sealing member 10. More specifically, the terminal surface 4t protrudes from the surface 10T of the sealing member 10 in the portion where the terminal 4 is provided. By doing in this way, it becomes easy to attach external electrodes, such as a bus bar, to the terminal surface 4t. In addition, if a convex part is provided in an external electrode and this convex part and the terminal surface 4t are connected, the terminal surface 4t may be dented rather than the surface 10T of the sealing member 10 (following embodiment). But the same).

  As shown in FIG. 4, the opening 6H of the housing 3 has a substantially rectangular shape in plan view. In the present embodiment, the opening 6H has a large aspect ratio (length: width is greater than 1: 1). The terminal surface 4i of the terminal 4 attached to the lid 3T faces the opening 6H. By making the terminal 4 a member having a rectangular shape in plan view, it is possible to easily secure a cross-sectional area through which the current of the terminal 4 passes even in the case 3 having the opening 6H having a large aspect ratio. .

  The terminal 4 is preferably made of a metal having good spreadability. In this embodiment, the terminal 4 is pure aluminum or an aluminum alloy, but the properties may be adjusted by heat treatment. In the present embodiment, A1050-O (pure aluminum is annealed to the softest state) is used. By doing in this way, the terminal 4 can ensure sufficient spreadability.

  The reason why it is preferable that the terminal 4 is made of a metal having good spreadability is as follows. The terminal 4 is molded integrally with the lid 3T by the resin sealing member 10, and then contracts when the resin is cured. Due to the shrinkage of the resin, the sealing member 10 and the terminal 4 may be separated. Moreover, even when both are not separated, there is a possibility that a gap is generated between them. For this reason, by manufacturing the terminal 4 with a material having good extensibility, when the shrinkage due to the curing of the resin occurs, the terminal 4 is deformed following the contraction of the resin (sealing member 10) (for example, plasticity). Deformation). Then, separation between the sealing member 10 and the terminal 4 and generation of a gap are avoided. By doing in this way, the fall of the yield at the time of integrally molding the lid | cover 3T, the sealing member 10, and the terminal 4 can be suppressed. Moreover, it can suppress that a gap | interval generate | occur | produces between the sealing member 10 and the terminal 4, and can also ensure both sealing performance.

  In this embodiment, for example, the proof stress (for example, 0.2% proof stress, the same applies hereinafter) of the terminal 4 (material of the terminal 4) is made smaller than the proof strength of the sealing member 10 (material of the sealing member). At this time, it is preferable that the proof stress of the terminal 4 is smaller than the bonding strength between the terminal 4 and the sealing member 10. By doing in this way, isolation | separation with the terminal 4 and the sealing member 10 and generation | occurrence | production of the clearance gap between both can be suppressed more reliably. In order to avoid the occurrence of a gap due to the shrinkage of the sealing member 10, the proof strength of the lid 3 T is made smaller than the proof strength of the sealing member 10 instead of making the proof strength of the terminal 4 smaller than the proof strength of the sealing member 10. May be. Since the lid 3T needs a certain strength as a structural member, the proof strength of the terminal 4 is made smaller than the proof strength of the sealing member 10 rather than the proof strength of the sealing member 10. Is preferred. Next, the pressure regulating valve 40 as the pressure regulating mechanism will be described.

<Pressure control valve>
FIG. 11 is a cross-sectional view of the pressure regulating valve. FIG. 12 is a perspective view including a cross section of the pressure regulating valve. In the power storage device 1, activated carbon is used for the first polarizable electrode 24 </ b> A and the second polarizable electrode 24 </ b> B. ) Is electrolyzed to generate gas. That is, gas is generated in the power storage device 1 by an electrochemical reaction. This gas increases the pressure in the storage chamber 6. For this reason, the pressure regulating valve 40 of the sealing member 10 releases the gas generated in the storage chamber 6 from the storage chamber 6 to the outside of the housing 3, and suppresses the pressure increase in the storage chamber 6.

  In the present embodiment, the pressure regulating valve 40 includes a valve case 41, a shaft 42, a gas passage 43, a valve body 45, and a stopper 46. Among these, the valve case 41 and the shaft 42 are molded integrally with the sealing member 10. The valve case 41 is an annular portion protruding from the sealing member 10 and has an opening 40Ho. A shaft 42 is formed at the center of the opening 40Ho. A valve body 45 which is a flexible member such as rubber is attached between the valve case 41 and the shaft 42. An annular stopper 46 is attached to the shaft 42 side of the valve body 45 to prevent the valve body 45 from dropping from the valve case 41. The pressure regulating valve 40 may not have the stopper 46.

  A plurality of gas passages 43 penetrates from the storage chamber 6 side (sealing member inner side 10I) of the sealing member 10 toward the opening 40Ho of the valve case 41. The plurality of gas passages 43 communicate the storage chamber side opening 40Hi that opens to the sealing member inner side 10I and the opening 40Ho of the valve case 41. For this reason, the storage chamber 6 communicates with the outside of the storage chamber 6 through a plurality of gas passages 43. The plurality of gas passages 43 are annularly arranged as shown in FIG. The shaft 42 is disposed at the center of the plurality of gas passages 43 disposed in an annular shape.

  The valve body 45 described above is in contact with the shaft 42 to close the opening of the gas passage 43 (opening on the opening 40Ho side of the valve case 41). Since the valve body 45 is a flexible member, when the pressure in the storage chamber 6 rises and exceeds the pressure generated by the valve body 45 pressing the shaft 42, there is a gap between the valve body 45 and the shaft 42. Occurs. From this gap, the gas in the storage chamber 6 is discharged through the gas passage 43. With such a structure, the pressure regulating valve 40 releases the gas generated in the storage chamber 6 from the storage chamber 6 to the outside of the housing 3 to suppress an increase in pressure in the storage chamber 6. The pressure regulating valve 40 is not limited to such a structure.

  In the present embodiment, the pressure regulating valve 40 includes a gas-liquid separation membrane 47 that separates gas and liquid and allows only gas to pass between the storage chamber 6 and the valve body 45. By doing so, the electrolyte solution in the storage chamber 6 is restrained from moving toward the valve body 45 by the gas-liquid separation membrane 47, so that the electrolyte solution in the storage chamber 6 becomes free from the valve body 45 and the shaft 42. Leakage from the gap can be suppressed. As the gas-liquid separation membrane 47, for example, mesh-like PTFE (Poly Tetra Fluoro Ethylene) can be used, but is not limited thereto. In the present embodiment, the gas-liquid separation membrane 47 is arranged on either the storage chamber 6 side of the storage chamber side opening 40Hi or on the shaft 42 side of the storage chamber side opening 40Hi. The former arrangement is preferable because the performance degradation of the gas-liquid separation membrane 47 can be made relatively small. In the latter arrangement, the gas-liquid separation membrane 47 can be accommodated inside the storage chamber side opening 40Hi, so that the gas-liquid separation membrane 47 is relatively easy to install.

  As described above, in the present embodiment, the resin sealing member 10 is interposed between the lid 3T and the terminal 4, and at least a part of the pressure regulating valve 40, the lid 3T, the terminal 4, and the sealing member 10 are provided. Mold in one piece. By doing in this way, the number of parts of the electrical storage apparatus 1 can be reduced.

(Embodiment 2)
FIG. 13 is a side view of the power storage device according to the second embodiment. FIG. 14 is a perspective view of a housing and a storage cell included in the power storage device according to the second embodiment. FIG. 15 is an electric circuit diagram of the power storage device according to the second embodiment. 16 and 17 are perspective views illustrating a lid of the power storage device according to the second embodiment. The power storage device 1A includes two storage chambers (first storage chamber 6A and second storage chamber 6B) and two storage cells (first storage cell 2A and second storage cell 2B). Different from the one power storage device 1. Other structures of the power storage device 1A according to the second embodiment are the same as those of the power storage device 1 of the first embodiment.

<Outline of power storage device>
As shown in FIG. 13, the housing 3A includes a first storage chamber 6A and a second storage chamber 6B. Both are divided by the partition part 8 provided in the housing | casing 3A. As shown in FIGS. 13 and 14, the first storage cell 6A is stored in the first storage chamber 6A, and the second storage cell 2B is stored in the second storage chamber 6B. As shown in FIG. 14, the first storage cell 2A is stored in the first storage chamber 6A from the opening 6AH of the first storage chamber 6A, and the second storage cell 2B has the opening 6BH of the second storage chamber 6B. Stored. The structure of the first storage cell 2A and the second storage cell 2B is the same as that of the storage cell 2 according to the first embodiment.

  In the power storage device 1A, a resin sealing member 10A in which a part of a pressure regulating valve 40A as a pressure regulating mechanism is formed is integrally molded together with a lid 3T attached to the housing 3A and terminals 4a and 4b. As shown in FIG. 15, the terminal 4a is electrically connected to the second lead portion 22E of the first storage cell 2A via the second connection conductor 26 shown in FIG. A second lead portion 22E of the second storage cell 2B is electrically connected to the terminal 4b via a second connection conductor 26 shown in FIG. The second lead portion 21E of the first power storage cell 2A and the second power storage cell 2B is electrically connected to the lid 3T through the first connection conductor 25.

  The first power storage cell 2A and the second power storage cell 2B included in the power storage device 1A illustrated in FIG. 15 each have an inter-terminal voltage of E, and a terminal voltage of the power storage device 1 (voltage between the terminal 4a and the terminal 4b). Is 2 × E. As shown in FIG. 15, the power storage device 1 connects the first power storage cell 2A and the second power storage cell 2B in series via the first lead portion 21E and the conductor lid 3T, and via the second lead portion 22E. Are connected to the terminals 4a and 4b. The potential of lid 3T is half (E) of the voltage across terminals of power storage device 1A. Thus, the potential of the lid 3T becomes an intermediate potential of the power storage device 1A.

  The power storage device 1A has a structure in which a current flows through the lid 3T. With this structure, the power storage device 1A includes the first power storage cell 2A and the second power storage cell 2B as two power storage cells, but only two terminals 4a and 4b are connected to the outside. . The insulator for securing the insulation between the lid 3T and the terminals 4a and 4b may be the resin sealing member 10A. In addition, when individual power storage cells are connected in series, a conductor for connecting the power storage cells is necessary. However, the power storage device 1A electrically connects the first power storage cell 2A and the second power storage cell 2B via the lid 3T. Therefore, a conductor for connecting the storage cells is not necessary. For this reason, power storage device 1A can reduce the number of parts.

  In the power storage device 1A, the first polar body 21 of the first power storage cell 2A and the first polar body 21 of the second power storage cell 2B are connected to the lid 3T without a conductor connected to the outside. For this reason, 1 A of electrical storage apparatuses can reduce the number of the conductors connected outside when connecting the 1st electrical storage cell 2A and the 2nd electrical storage cell 2B in series. As a result, the power storage device 1A has a simple structure, so that the manufacturing cost is reduced and the reliability is improved. Further, since the lid 3T is made of a conductor, it has excellent electrical conductivity and thermal conductivity. In the present embodiment, since the lid 3T is an aluminum alloy, the electrical conductivity and thermal conductivity are good. In the power storage device 1A, the first power storage cell 2A and the second power storage cell 2B generate heat, but the first electrode body 21 is connected to the lid 3T having good thermal conductivity. For this reason, the heat generated in the first power storage cell 2 </ b> A and the second power storage cell 2 </ b> B is transmitted from the first polar body 21 to the lid 3 </ b> T and is radiated from the surface of the housing 3. For this reason, 1 A of electrical storage apparatuses have the advantage that heat dissipation performance is high. Note that unevenness or fins may be provided on the surface of the lid 3T. If it does in this way, since the surface area of the lid | cover 3T will become large, 1 A of electrical storage apparatuses will further improve heat dissipation performance.

  The power storage device 1A stores an electrolytic solution in the first storage chamber 6A and the second storage chamber 6B in addition to the first storage cell 2A and the second storage cell 2B. For this reason, the power storage device 1A seals the inside of the housing 3 by providing the sealing member 10 between the lid 3T and the terminals 4a and 4b. Since the terminals 4a and 4b and the lid 3T are all conductors, they need to be insulated. It is difficult to achieve both the sealing of the housing 3A and the lid 3T and the insulation between the housing 3A and the terminals 4a and 4b and to improve the reliability.

  When two storage cells are connected in series, it is necessary to use a total of four insulators for the sealing and insulation described above. In contrast, in the power storage device 1A, the first power storage cell 2A and the second power storage cell 2B are connected in series, but one sealing member 10A may be used for the above-described sealing and insulation. As described above, since the power storage device 1A can reduce the number of members used for the sealing and insulation described above, the reliability can be improved correspondingly, and the work used for the sealing and insulation described above can be reduced, and further the cost can be reduced. it can.

  A power storage device 1 </ b> A illustrated in FIG. 15 electrically connects the first power storage cell 2 </ b> A and the second power storage cell 2 </ b> B by the housing 3. The power storage device 1A is electrically connected by a pressure regulating valve 40A having gas passages 43A and 43B opened in the first storage chamber 6A and the second storage chamber 6B, respectively, storing the first storage cell 2A and the second storage cell 2B. The gas generated by the chemical reaction is released to the outside of the power storage device 1A. For this reason, when two electrical storage cells are connected in series, a pressure regulating valve is required for each electrical storage cell. As described above, the voltage between the terminals of the power storage device 1A is 2 × E, which is the same as when two power storage cells are connected in series. As described above, the power storage device 1A can halve the number of the pressure regulating valves 40 as compared with the power storage device 1A having the same inter-terminal voltage by connecting two power storage cells in series. Next, the sealing member 10A and the terminals 4a and 4b included in the lid 3T of the power storage device 1A will be described.

<Sealing member and terminal>
As shown in FIG. 16, the terminal surfaces 4at and 4bt are connected to external terminals such as bus bars, and the terminal surfaces 4at and 4bt protrude from the surface 10AT of the sealing member 10 in the portion where the terminals 4a and 4b are provided. Yes. By doing in this way, it becomes easy to attach external terminals, such as a bus bar, to the terminal surface 4i. As shown in FIG. 17, the terminal surfaces 4ai and 4bi of the terminals 4a and 4b, that is, the terminal surfaces 4ai and 4bi on the storage chamber 6 side are the surfaces 3Ti of the lid 3T on the first storage chamber 6A and the second storage chamber 6B side. Are disposed in the same plane, preferably in the same plane.

  The first electrode body 21 of the first storage cell 2A and the second storage cell 2B is electrically connected to the surface 3Ti on the storage chamber 6 side of the lid 3T through a first connection conductor 25 by a joining technique such as ultrasonic pressure connection. Connected. Further, the second pole body 22 of the first storage cell 2A is provided on the terminal surface 4ai via the second connection conductor 26, and the second pole of the second storage cell 2B is provided on the terminal surface 4bi via the second connection conductor 26. The body 22 is electrically connected by a joining technique such as ultrasonic pressure connection. For this reason, by arranging the terminal surfaces 4ai and 4bi and the surface 3Ti of the lid 3T substantially in the same plane, preferably in the same plane, the reference for joining the terminal surfaces 4ai and 4bi and the second connection conductor 26, and the lid The reference for joining the 3T surface 3Ti and the first connection conductor 25 can be made the same. By doing in this way, the positioning operation | work at the time of joining the terminal surfaces 4ai and 4bi and the 2nd connection conductor 26 and the positioning operation | work at the time of joining the surface 3Ti of the lid | cover 3T and the 1st connection conductor 25 are made easy. can do.

  The pressure regulating valve 40A included in the sealing member 10A includes gas passages 43A and 43B corresponding to the first storage chamber 6A and the second storage chamber 6B shown in FIGS. The gas passages 43A and 43B are connected to the outside of the first storage chamber 6A and the second storage chamber 6B via valve bodies. With such a structure, the pressure regulating valve 40A allows the first storage chamber 6A and the second storage chamber 6B to pass through the gas passages 43A and 43B when the gas pressure in the first storage chamber 6A and the second storage chamber 6B rises. Gas can be released to the outside.

  Further, the sealing member 10A has electrolyte solution inlets 11HA and 11HB corresponding to the first storage chamber 6A and the second storage chamber 6B shown in FIGS. The electrolytic solution is injected into the first storage chamber 6A and the second storage chamber 6B from the electrolyte injection ports 11HA and 11HB. Note that the electrolytic solution may be injected into the first storage chamber 6A and the second storage chamber 6B using the gas passages 43A and 43B.

  In the present embodiment, similarly to the first embodiment, a resin sealing member 10A is interposed between the lid 3T and the terminals 4a and 4b, and at least a part of the pressure regulating valve 40A, the lid 3T, the terminal 4a, 4b and the sealing member 10A are integrally molded. By doing in this way, the number of parts of power storage device 1A can be reduced.

  As mentioned above, although Embodiment 1 and 2 were demonstrated, this embodiment is not limited by the content mentioned above. In addition, the constituent elements of Embodiments 1 and 2 described above include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the above-described components can be appropriately combined. In addition, various omissions, substitutions, and changes of the components can be made without departing from the scope of the first and second embodiments.

1, 1A power storage device 2 power storage cell 2A first power storage cell 2B second power storage cell 2U power storage unit 3, 3A housing 3B bottom 3S side peripheral part 3T lid 3TE peripheral part 3TH opening 3Ti surface 4, 4a, 4b terminal 4B child Main body 4F Overhang portion 4FI Inside 4FS Outside 4S side portion 4i, 4t, 4ai, 4at, 4bi, 4bt Terminal surfaces 6H, 6AH, 6BH Opening portion 6 Storage chamber 6A First storage chamber 6B Second storage chamber 8 Partition portion 10, 10A Insulating member 10T, 10AT Surface 10I Sealing member inner side 11 Electrolyte injection part 11H Injection passage 11HA, 11HB Electrolyte injection inlet 21 1st pole body 21E 1st extraction part 22 2nd pole body 22E 2nd extraction part 23 Separator 24A First polarizable electrode 24B Second polarizable electrode 25 First connecting conductor 26 Second connecting conductor 40, 40A Pressure regulating valve 40Hi, 40Ho Opening 41 Valve case 2-axis 43 and 43A, 43B gas passage 45 the valve member 46 a stopper 47 gas-liquid separation membrane

Claims (10)

A chargeable / dischargeable storage cell having two polar bodies;
A container having an opening at one end, a housing for storing the storage cell;
One of the polar bodies is electrically connected, and a conductor lid attached to the opening;
A terminal of a conductor electrically connected to the other polar body and drawn out of the housing from the lid;
A pressure adjusting mechanism that is provided on the lid and adjusts the pressure inside the housing;
A sealing member that is interposed between the lid and the terminal, and at least a part of the pressure regulating mechanism is formed, and is molded integrally with the lid and the terminal;
A power storage device comprising:   The power storage device according to claim 1, wherein the yield strength of the terminal is smaller than the yield strength of the sealing member.   3. The power storage device according to claim 1, wherein the terminal has a substantially rectangular cross section orthogonal to the drawing direction and has the same size and shape throughout the drawing direction. The lid is a plate-shaped member,
2. The terminal has a flat surface on the inner side of the housing, and the flat surface of the terminal is arranged in a plane substantially the same as a surface of the lid on the inner side of the housing. 4. The power storage device according to any one of items 1 to 3.   5. The power storage device according to claim 1, wherein an outer side of the casing of the terminal protrudes from the sealing member.   The power storage device according to any one of claims 1 to 5, wherein the terminal is a plate-like member and has an overhang portion on an outer peripheral portion.   The power storage device according to claim 6, wherein the projecting portion has an outer thickness larger than an inner thickness.   The power storage device according to claim 1, wherein the pressure regulating mechanism includes a gas-liquid separation membrane on the housing side.   The power storage device according to claim 1, wherein the opening has a substantially rectangular shape in plan view. A chargeable / dischargeable storage cell having two polar bodies;
A container having an opening at one end, a housing for storing the storage cell;
One of the polar bodies is electrically connected, and a conductor lid attached to the opening;
A terminal of a conductor electrically connected to the other polar body and drawn out of the housing from the lid;
A pressure adjusting mechanism that is provided on the lid and adjusts the pressure inside the housing;
A resin sealing member interposed between the lid and the terminal, and at least a part of the pressure regulating mechanism is formed, and molded integrally with the lid and the terminal;
Including
The terminal has a substantially rectangular cross section perpendicular to the pulling direction, has the same size and shape throughout the pulling direction, and the proof stress is smaller than the proof strength of the sealing member and the bonding strength between the sealing member and the terminal. A power storage device.

Images