Patent Publication Number: US-2023142307-A1

Title: Electrical storage module

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is the U.S. National Phase under 35 U.S.C. § 371 of International Patent Application No. PCT/JP2021/011760, filed on Mar. 22, 2021, which in turn claims the benefit of Japanese Patent Application No. 2020-051852, filed on Mar. 23, 2020, the entire content of each of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to an electrical storage module. 
     BACKGROUND ART 
     A battery case that includes: a tray member for supporting a battery; a cover member fixed to the tray member so as to be superposed on the tray member; and a gasket interposed between the tray member and the cover member is described in Patent Literature 1, for example. 
     In the battery case of Patent Literature 1, a tray-side flange part is provided to a peripheral wall of the tray member. In the joint face of the tray-side flange part, a recessed groove part is formed along the peripheral direction, and a gasket is accommodated in this groove part. Meanwhile, in the cover member, a cover-side flange part is formed at the periphery of a cover body part. When the cover member is joined to the tray member, the joint face of the cover-side flange part comes into contact with the joint face of the tray member-side flange part, and comes into contact with the gasket. 
     CITATION LIST 
     Patent Literature 
     [PTL 1] Japanese Laid-Open Patent Publication No. 2012-124131 
     SUMMARY OF THE INVENTION 
     Problems to Be Solved by the Invention 
     In the above battery case, a waterproof property between the tray member and the cover member is ensured by the gasket. However, when a battery unit configured by a battery being housed in the above battery case is used in an environment in which the battery unit is more likely to be exposed to water, a higher waterproof property is required so as to prevent water from entering the inside of the battery case. 
     In view of the above problem, an object of the present invention is to provide an electrical storage module that can improve the waterproof property between a case in which an electrical storage device is housed, and a lid which covers an opening part of the case. 
     Solution to the Problems 
     An electrical storage module according to a major aspect of the present invention includes: an electrical storage device; a case in which the electrical storage device is housed; and a lid configured to cover an opening part of the case. Here, the case includes a recess at an outer periphery of the opening part, the lid includes a first protrusion configured to be inserted into the recess, and a sealing member is present between the first protrusion and the recess. 
     Advantageous Effects of the Invention 
     According to the present invention, waterproof property between the case in which the electrical storage device is housed and the lid which covers the opening part of the case can be improved. 
     The effects and the significance of the present invention will be further clarified by the description of the embodiment below. However, the embodiment below is merely an example for implementing the present invention. The present invention is not limited by the description of the embodiment below in any way. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an electrical storage module according to an embodiment. 
         FIG.  2    is an exploded perspective view of the electrical storage module according to the embodiment. 
         FIG.  3    is a perspective view of electrical storage devices, a device holder, a circuit board, and a lid, which have been integrated, viewed from the front and below, according to the embodiment. 
         FIGS.  4 A to  4 C  are respectively a front perspective view, a bottom perspective view, and a plan view of the lid having a connector formed integrally therewith, according to the embodiment. 
         FIGS.  5 A and  5 B  are respectively enlarged partial cross-sectional views of a front portion of the lid cut at the positions of a line A-A′ and a line B-B′ in  FIG.  4 B , according to the embodiment. 
         FIGS.  6 A and  6 B  are respectively a front perspective view and a rear perspective view of a case according to the embodiment. 
         FIG.  7    is a plan view of the case according to the embodiment. 
         FIG.  8 A  is an enlarged partial cross-sectional view of the case cut along a line C-C′ in  FIG.  7   , according to the embodiment, and  FIG.  8 B  is an enlarged partial cross-sectional view of the case in a state where an adhesive has been injected into a groove part, cut along the line C-C′ in  FIG.  7   , according to the embodiment. 
         FIGS.  9 A and  9 B  are enlarged partial cross-sectional views of a front portion of the electrical storage module cut at the same position as the line A-A′ in  FIG.  4 B , according to the embodiment. 
         FIG.  10    is an enlarged partial cross-sectional view of a front portion of the electrical storage module cut at the same position as the line B-B′ in  FIG.  4 B , according to the embodiment. 
         FIGS.  11 A and  11 B  are diagrams for describing a configuration of an electrical storage module according to a modification. 
         FIGS.  12 A and  12 B  are diagrams for describing a configuration of a case according to a modification. 
     
    
    
     It is noted that the drawings are solely for description and do not limit the scope of the present invention in any way. 
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Hereinafter, an electrical storage module  1  according to the present embodiment will be described with reference to the drawings. For convenience, front, rear, left, right, up, and down directions are indicated in the drawings, as appropriate. It should be noted that the directions in the drawings merely indicate relative directions with respect to the electrical storage module  1 , and do not indicate absolute directions. In addition, for convenience of description, some components are denoted by names according to directions in the drawings, such as “bottom face part”, “front side face part”, and the like. 
     In the present embodiment, an inner peripheral bottom face  402   a  corresponds to “sixth face part” described in the claims, and an outer peripheral bottom face  402   b  corresponds to “third face part” described in the claims. Mounting holes  411 ,  414  correspond to “fitting hole” described in the claims. Further, an outer peripheral rib  451  corresponds to “second protrusion” described in the claims. Further, a rib  460  corresponds to “first protrusion” described in the claims. Further, a leading end face  461   a  corresponds to “fourth face part” described in the claims. Further, an inner peripheral upper face  531   a  corresponds to “first face part” described in the claims. Further, an outer peripheral upper face  531   b  corresponds to “second face part” described in the claims. Further, a groove part  532  corresponds to “recess” described in the claims. Further, an inner peripheral side face  532   b  corresponds to “fifth face part” described in the claims, and “side face” described in claim 12 of the claims. Further, an outer peripheral side face  532   c  corresponds to “side face” described in the claims. Further, emboss processing  533  corresponds to “surface roughening processing” described in the claims. Further, an inner peripheral wall face  507  corresponds to “inner wall face” described in the claims. 
     However, the above description is merely for providing correspondence between the configurations described in the claims and the configurations of the embodiment. This correspondence does not limit the invention described in the claims to the configurations of the embodiment in any way. 
       FIG.  1    is a perspective view of the electrical storage module  1  according to the present embodiment.  FIG.  2    is an exploded perspective view of the electrical storage module  1  according to the present embodiment. 
     The electrical storage module  1  includes five electrical storage devices  100 , a device holder  200 , a circuit board  300 , a lid  400 , and a case  500 . A connector  600  is formed integrally with the lid  400 . The device holder  200  in which the five electrical storage devices  100  are held, the circuit board  300 , and the lid  400  are integrated, then, the device holder  200  in which the electrical storage devices  100  are held, and the circuit board  300  are housed in the case  500 , and an opening part  506  of the case  500  is covered by the lid  400 . The lid  400  is fixed to the case  500  by four screws  700 . The lid  400  and the case  500  are adhered to each other by an adhesive  800  provided in an annular shape at the outer periphery of the opening part  506 . The adhesive  800  that has been cured functions as a sealing member  800  for providing water-sealing between the lid  400  and the case  500 . 
     The electrical storage module  1  is used in various electronic apparatuses, electrical apparatuses, industrial apparatuses, automobiles, and the like, and provides assistance, backup, and the like of power. For example, when the electrical storage module  1  is mounted to an automobile, the electrical storage devices  100  can be charged by power supplied by a battery of the automobile. 
       FIG.  3    is a perspective view of the electrical storage devices  100 , the device holder  200 , the circuit board  300 , and the lid  400 , which have been integrated, viewed from the front and below, according to the present embodiment. 
     Each electrical storage device  100  is an electric double layer capacitor, for example. The electrical storage device  100  may be a capacitor, such as a lithium ion capacitor, other than an electric double layer capacitor. An electrical storage device  100  in which a conductive polymer is used as an active material of the positive electrode may be adopted. Examples of the conductive polymer include polyaniline, polypyrrole, or polythiophene, derivatives thereof, and the like. A plurality of types of conductive polymers may be used. 
     Each electrical storage device  100  includes: a container  110  having a slender bottomed cylindrical shape and containing a device element (not shown) and an electrolytic solution; a sealing body  120  which is formed from an elastic material containing a rubber component and which seals the opening of the container  110 ; and a positive electrode lead terminal  130  and a negative electrode lead terminal  140  which are drawn from the sealing body  120  to the outside. The positive electrode lead terminal  130  is electrically connected to the positive electrode of the device element, and the negative electrode lead terminal  140  is electrically connected to the negative electrode of the device element. 
     The device holder  200  is formed from a resin material such as polybutylene terephthalate (PBT) or polyphenylene sulfide (PPS) . 
     The device holder  200  includes five accommodation parts  210  continuous in the left-right direction so as to hold the five electrical storage devices  100  in a state of being arranged in the left-right direction. Each accommodation part  210  is recessed in a semicircular arc shape so as to be able to accommodate a half of the peripheral face of the electrical storage device  100 . Each accommodation part  210  is provided with pairs of claw parts  211  at three places in the up-down direction. Each claw part  211  is curved so as to have the same curvature as that of the holding face in the circular arc shape of the accommodation part  210 , and protrudes toward the inner side of the accommodation part  210 . The holding face of each accommodation part  210  is also provided with pairs of claw parts (not shown) at two places. Each electrical storage device  100  is sandwiched by the pairs of claw parts  211  at the three places, and the pairs of claw parts at the two places, thereby being held in the corresponding accommodation part  210 . 
     At the left and right side faces of the device holder  200 , insertion ribs  220  extending in the up-down direction are formed. At the bottom face of the device holder  200 , an insertion rib  230  extending in the left-right direction is formed. 
     The circuit board  300  has a substantially rectangular shape that is long in the left-right direction. The device holder  200  is fixed to the circuit board  300  by a so-called snap fit structure in which claw parts  240  provided at the left and right side faces of the device holder  200  and each having a hook-shaped leading end are inserted in mounting holes  301  of the circuit board  300 . The device holder  200  and the circuit board  300  overlap each other in the front-rear direction such that an upper portion of the circuit board  300  protrudes upward and a lower portion of the device holder  200  protrudes downward with respect to each other. 
     In the circuit board  300 , a pattern wiring (not shown) for connecting the five electrical storage devices  100  in series or in parallel is formed. The positive electrode lead terminal  130  and the negative electrode lead terminal  140  of each electrical storage device  100  are connected to the pattern wiring by soldering. In the circuit board  300 , a charging circuit (not shown) for charging each electrical storage device  100  by supply of power from an external battery or the like is disposed. In  FIG.  2    and  FIG.  3   , an FET (Field effect transistor)  302  included in the charging circuit, and a heat sink  303  for dissipating heat from the FET  302  are shown. 
       FIGS.  4 A to  4 C  are respectively a front perspective view, a bottom perspective view, and a plan view of the lid  400  having the connector  600  formed integrally therewith, according to the present embodiment.  FIGS.  5 A and  5 B  are respectively enlarged partial cross-sectional views of a front portion of the lid  400  cut at the positions of a line A-A′ and a line B-B′ in  FIG.  4 B , according to the present embodiment. 
     The lid  400  is formed from a resin material such as polybutylene terephthalate (PBT) or polyphenylene sulfide (PPS). The lid  400  is formed in a plate shape that is long in the left-right direction and substantially rectangular, and four corner portions thereof at the front, rear, left, and right have circular arc shapes. As for the lid  400 , a top face  401  thereof is the obverse side, and a bottom face  402  thereof is the reverse side. 
     Mounting holes  411  to  414  are formed in the lid  400  at four corner portions thereof. Out of the four mounting holes  411  to  414 , the mounting hole  411  at the left-front corner portion has an elongated circular shape, and the other mounting holes  412  to  414  at the right-front, left-rear, and right-rear corner portions each have a circular shape. The diameter of the mounting hole  414  at the right-rear corner portion is greater than the diameter of the mounting holes  412 ,  413  at the right-front and left-rear corner portions. As for the mounting hole  411 , the longitudinal direction thereof is parallel to the diagonal connecting the right-front corner and the left-rear corner of the lid  400 , and the diameter in the short direction is equal to the diameter of the mounting hole  414 . 
     In the lid  400 , a ventilation opening part  420  is provided on the left side with respect to the center. The ventilation opening part  420  includes: a ventilation hole  421  having a circular shape; ribs  422 ,  423  having annular shapes and formed around the ventilation hole  421  on the top face  401  side and the bottom face  402  side of the lid  400 ; and a ventilation membrane  424  attached to the rib  423  and covering the ventilation hole  421 . The ventilation membrane  424  is a member in which a water-repellent/oil-repellent membrane is formed by laminating a PTFE porous membrane on a substrate composed of a non-woven fabric or a woven fabric made of polyethylene terephthalate (PET) which has been subjected to water-repellent/oil-repellent treatment. The ventilation membrane  424  has a characteristic of repelling water and allowing air to pass therethrough. 
     In the lid  400 , a protruding part  430  having a substantially rectangular frame shape is provided along the outer peripheral edge of the lid  400  so as to project from the top face  401 . The protruding part  430  is provided so as to avoid the peripheries of the four mounting holes  411  to  414 . The protruding part  430  has a thickness-reduced structure. 
     In the lid  400 , a rib group  440  is provided in a region on the inner side of the protruding part  430  on the top face  401 . The rib group  440  has a configuration in which a plurality of ribs  441  extending in the left-right direction and a plurality of ribs  442  extending in the front-rear direction are combined as appropriate, and is connected to the protruding part  430 , the rib  422  of the ventilation opening part  420 , and the connector  600 . 
     On the bottom face  402  of the lid  400 , an inner lid part  450  is provided so as to rise, as a whole, from the bottom face  402 . The inner lid part  450  has a shape that corresponds to the shape of the opening part  506  of the case  500 , i.e., a rectangular shape that has large circular arcs at four corner portions. The inner lid part  450  enters to the inner side of an inner peripheral wall face  507  of the case  500  when the lid  400  is attached to the case  500 . The inner lid part  450  includes an outer peripheral rib  451  having an annular shape and forming an outer peripheral edge portion of the inner lid part  450 . The inner lid part  450  includes, on the inner side of the outer peripheral rib  451 , a thick portion  452  having a quadrangular shape and increasing the thickness of the region on the reverse side of the connector  600 , and includes a rib group  453  in a region other than the thick portion  452 . The rib group  453  has a configuration in which: a rib  454  having an annular shape and surrounding the periphery of the rib  423  of the ventilation opening part  420 ; a plurality of ribs  455  extending in the left-right direction; and a plurality of ribs  456  extending in the front-rear direction, are combined. The rib group  453  is connected to the outer peripheral rib  451  and the thick portion  452 . 
     Further, on the bottom face  402  of the lid  400 , a rib  460  having an annular shape that is long in the left-right direction and short in the front-rear direction is formed at the outer periphery of the inner lid part  450 . The rib  460  has a substantially quadrate shape in a cross-section thereof, and both corner portions at the leading end are chamfered into circular arc shapes. The height of rib  460  is smaller than the height of the outer peripheral rib  451  of the inner lid part  450 . As for the bottom face  402  of the lid  400 , the position of a face  402   a  (hereinafter, referred to as “inner peripheral bottom face  402   a ”) on the inner side with respect to the rib  460  is lower than the position of a face  402   b  (hereinafter, referred to as “outer peripheral bottom face  402   b ”) on the outer side with respect to the rib  460 . In the rib  460 , a projection  461  projecting toward the inner lid part  450  side, i.e., the inner side of the lid  400 , is formed at a center portion in the left-right direction (the longitudinal direction of the lid  400 ) on each of the front side and the rear side. When the lid  400  has been attached to the case  500 , a leading end face  461   a  of the projection  461  faces the opening part  506  side in a direction along the opening face of the opening part  506 . 
     In the lid  400 , mounting bosses  470  are provided at left and right end portions of the inner lid part  450 . In each mounting boss  470 , a screw hole  471  that is open to the rear is formed. 
     The connector  600  is formed integrally with the lid  400  and includes a housing  610  and a plurality of terminals  620 . The housing  610  has a substantially rectangular parallelepiped box shape that is long in the left-right direction and of which the upper face is open. A part of the lid  400  is shared as a bottom face part  611  of the housing  610 . A peripheral face part  612  composed of the front, rear, left, and right side faces of the housing  610  projects from the top face  401  of the lid  400 . The plurality of terminals  620  are embedded, by insert molding, in the bottom face part  611  of the housing  610  so as to be arranged in the left-right direction. As for each terminal  620 , one end side is accommodated in the housing  610 , and the other end side projects to the outside from the inner lid part  450  on the reverse side of the lid  400 . The other end side of each terminal  620  is bent in a substantially L-shape. 
     As shown in  FIG.  3   , the lid  400  is fixed to an upper end portion of the circuit board  300  as a result of the two mounting bosses  470  on the reverse side being mounted to the circuit board  300  by screws (not shown). Each terminal  620  of the connector  600  is connected to the pattern wiring of the circuit board  300 . Accordingly, the five electrical storage devices  100  and the terminals  620  for outputting power from these electrical storage devices  100  are electrically connected to each other. Further, the charging circuit and the terminal  620  for supplying power from a battery to this charging circuit are electrically connected to each other. 
       FIGS.  6 A and  6 B  are respectively a front perspective view and a rear perspective view of the case  500  according to the present embodiment.  FIG.  7    is a plan view of the case  500  according to the present embodiment.  FIG.  8 A  is an enlarged partial cross-sectional view of the case  500  cut along a line C-C′ in  FIG.  7   , according to the present embodiment.  FIG.  8 B  is an enlarged partial cross-sectional view of the case  500  in a state where the adhesive  800  has been injected into a groove part  532 , cut along the line C-C′ in  FIG.  7   , according to the present embodiment. 
     The case  500  is formed from a resin material such as polybutylene terephthalate (PBT) or polyphenylene sulfide (PPS). The case  500  is formed in a substantially rectangular parallelepiped box shape that is wide in the left-right direction and thin in the front-rear direction. The case  500  includes a bottom face part  501 , a front side face part  502 , a rear side face part  503 , a left side face part  504 , and a right side face part  505 , and has the opening part  506  at the upper end face. In the case  500 , four corner portions between the side face parts  502  to  505  are formed in large circular arc shapes. Thus, the shapes of the bottom face part  501  and the opening part  506  of the case  500  are rectangles having large circular arc shapes at four corner portions. 
     In an upper portion and a lower portion of each of the left side face part  504  and the right side face part  505 , mounting bosses  510  each having a substantially round columnar shape and facing rearward are provided. A nut  511  made of metal and having a cylindrical shape is embedded in each mounting boss  510 . 
     Inside the case  500 , on the inner wall face of the bottom face part  501 , a bottom face holder fixation groove  522  realized by two ribs  521  extending in the left-right direction is provided at three places in the left-right direction. Further, at each of the left side face part  504  and the right side face part  505 , a side face holder fixation groove  524  and a board fixation groove  525  realized by three ribs  523  extending in the up-down direction are provided. The bottom face holder fixation grooves  522  and the side face holder fixation grooves  524  are at the same position in the front-rear direction. When the device holder  200  holding the electrical storage devices  100  and the circuit board  300  have been housed in the case  500 , the insertion ribs  220  at the side faces of the device holder  200  are inserted into the side face holder fixation grooves  524 , and the insertion rib  230  at the bottom face of the device holder  200  is inserted into the bottom face holder fixation grooves  522 . Further, a left end portion and a right end portion of the circuit board  300  are respectively inserted into the board fixation grooves  525  of the left side face part  504  and the right side face part  505 . Accordingly, the device holder  200  holding the electrical storage devices  100  and the circuit board  300  are fixed inside the case  500 . 
     The inner peripheral wall face  507  is formed by the inner wall faces of the four, i.e., the front, rear, left, and right, side face parts  502 ,  503 ,  504 ,  505  of the case  500 . 
     In the case  500 , in an upper end portion thereof, a lid attachment part  530  that has a flange shape and to which the lid  400  is attached is provided. The lid attachment part  530  is recessed into a shape corresponding to the external shape of the lid  400 , so as to be able to accommodate the lid  400 . An upper face  531  of the lid attachment part  530  serves as an attachment face to which the lid  400  is attached. In the upper face  531  of the lid attachment part  530 , the groove part  532 , having an annular shape, that circles along the opening edge of the opening part  506  is formed at the outer periphery of the opening part  506 . The groove part  532  is chamfered such that the corner portion between a bottom face  532   a  and a side face  532   b  (hereinafter, referred to as “inner peripheral side face  532   b ”) on the inner peripheral side, and the corner portion between the bottom face  532   a  and a side face  532   c  (hereinafter, referred to as “outer peripheral side face  532   c ”) on the outer peripheral side become R-chamfers. As for the upper face  531  of the lid attachment part  530 , the position of a face  531   a  (hereinafter, referred to as “inner peripheral upper face  531   a ”) on the inner side with respect to the groove part  532  is lower than the position of a face  531   b  (hereinafter, referred to as “outer peripheral upper face  531   b ”) on the outer side with respect to the groove part  532 . Accordingly, as for the groove part  532 , the height of the inner peripheral side face  532   b  is smaller than the height of the outer peripheral side face  532   c . The corner portion between the inner peripheral side face  532   b  and the inner peripheral upper face  531   a  is chamfered so as to be an R-chamfer, and the corner portion between the outer peripheral side face  532   c  and the outer peripheral upper face  531   b  is not chamfered and is angular. 
     In the groove part  532 , the entire region of the bottom face  532   a , the inner peripheral side face  532   b , and a region, in the outer peripheral side face  532   c , up to the upper end position of the inner peripheral side face  532   b  are faces having been subjected to emboss processing  533  as surface roughening processing (see  FIG.  8 A ). 
     In the upper face  531  of the lid attachment part  530 , screw holes  534   a  to  534   d  having circular shapes are respectively formed at left-front, right-front, left-rear, and right-rear corner portions. Bosses  535 ,  536  having round columnar shapes are formed at the left-front and right-rear corner portions, and the screw holes  534   a ,  534   d  at the left-front and right-rear corner portions are formed in the bosses  535 ,  536 . The outer diameter of each boss  535 ,  536  is substantially equal to the inner diameter of the mounting hole  414  at the right-rear corner portion of the lid  400 . In the lid attachment part  530 , a mounting boss  537  is provided at the position of each screw hole  534   a  to  534   d , and each screw hole  534   a  to  534   d  extends to the inside of the mounting boss  537 . 
     As shown in  FIG.  8 B , the adhesive  800  is injected into the groove part  532  of the case  500 , before the lid  400  is attached to the case  500 . At this time, the position of the boundary of the portion of the emboss processing  533  at the inner peripheral side face  532   b  and the outer peripheral side face  532   c  of the groove part  532  serves as a mark for the injection amount, and the adhesive  800  is injected up to the position of the boundary. 
     As the adhesive  800 , a moisture-curing silicon adhesive, a heat-curing epoxy adhesive, or the like can be used, for example. The adhesive  800  has a characteristic in which a state where the viscosity of the adhesive  800  is low changes to a state where the viscosity is high. 
     The adhesive  800  is injected, in a state where the viscosity is low, into the groove part  532 . Then, in a case of a moisture-curing silicon adhesive, the adhesive  800  reacts with moisture in the atmosphere to be cured, and in a case of a heat-curing epoxy adhesive, the adhesive  800  is cured by being heated, to exhibit adhesiveness, and the viscosity of the adhesive  800  becomes high (hardens). 
     After the adhesive  800  has been injected into the groove part  532  of the case  500 , and before the adhesive  800  is cured, the device holder  200  holding the electrical storage devices  100  and the circuit board  300  are housed in the case  500 , and the lid  400  is attached to the lid attachment part  530  of the case  500 . The opening part  506  of the case  500  is closed by the lid  400 . At this time, the bosses  535 ,  536  at the left-front and right-rear corner portions of the lid attachment part  530  are fitted in the mounting holes  411 ,  414  at the left-front and right-rear corner portions of the lid  400 . Accordingly, the lid  400  is positioned with respect to the lid attachment part  530 , i.e., the case  500 , in the front-rear and left-right directions (in directions perpendicular to the attachment direction). The respective mounting holes  411  to  414  of the lid  400  and the respective screw holes  534   a  to  534   d  of the case  500  are aligned with each other. The screws  700  passed through the respective mounting holes  411  to  414  are fastened to the respective screw holes  534   a  to  534   d . In this manner, the lid  400  is fixed to the case  500  by the four screws  700 . When the adhesive  800  has been cured, the lid  400  and the case  500  are adhered to each other by the adhesive  800 . Accordingly, the electrical storage module  1  is assembled. 
       FIGS.  9 A and  9 B  are enlarged partial cross-sectional views of a front portion of the electrical storage module  1  cut at the same position as the line A-A′ in  FIG.  4 B , according to the present embodiment.  FIG.  10    is an enlarged partial cross-sectional view of a front portion of the electrical storage module  1  cut at the same position as the line B-B′ in  FIG.  4 B , according to the present embodiment. 
     When the lid  400  has been attached to the case  500 , the outer peripheral bottom face  402   b  of the lid  400  comes into contact with the outer peripheral upper face  531   b  of the case  500 , and the inner peripheral bottom face  402   a  of the lid  400  is opposed to the inner peripheral upper face  531   a  of the case  500  with a predetermined distance therebetween. In addition, the rib  460  of the lid  400  is inserted into the groove part  532  of the case  500 . The rib  460  is pushed into the adhesive  800  which is present in the groove part  532  and which has a high viscosity before being cured. Accordingly, the adhesive  800  is pushed toward the bottom face  532   a  side of the groove part  532 , to be deformed so as to be spread sideways, thereby entering between the rib  460  and the outer peripheral side face  532   c  of the groove part  532  and entering between the rib  460  and the inner peripheral side face  532   b  of the groove part  532 . In the case  500 , the inner peripheral upper face  531   a  is at a position lower than that of the outer peripheral upper face  531   b , and thus, the groove part  532  is shallow on the inner peripheral upper face  531   a  side. Therefore, as shown in  FIG.  9 A , the adhesive  800  further enters between the inner peripheral bottom face  402   a  of the lid  400  and the inner peripheral upper face  531   a . The adhesive  800  is cured in a state of being deformed as described above. The cured adhesive  800  is present in a state of being in close contact with the lid  400  and the case  500 , between the rib  460  and the groove part  532  and between the inner peripheral bottom face  402   a  and the inner peripheral upper face  531   a , and functions as a sealing member  800  for providing water-sealing between the lid  400  and the case  500 . The sealing member  800  has been deformed in a shape like a “U” as a result of the rib  460  having entered the sealing member  800 , and a seal length L is longer than the width of the bottom face  532   a  of the groove part  532 . Thus, since the seal length L is made long, the waterproofing effect by the sealing member  800  can be expected to be enhanced. 
     The inner lid part  450 , i.e., the outer peripheral rib  451 , of the lid  400  is inserted inside the case  500 . A gap having a predetermined distance D1 is formed between the outer peripheral rib  451  and the inner peripheral wall face  507  of the case  500 . Therefore, as shown in  FIG.  9 B , if the injection amount of the adhesive  800  into the groove part  532  is adjusted, when the lid  400  is attached to the case  500 , the adhesive  800  can be caused to enter also between the outer peripheral rib  451  and the inner peripheral wall face  507  of the case  500 , whereby the seal length L of the sealing member  800  can be made longer. The distance D1 between the outer peripheral rib  451  and the inner peripheral wall face  507  is smaller than a distance D2 between the leading end of the rib  460  and the bottom face  532   a  of the groove part  532 . Therefore, increase in the amount of the sealing member  800 , i.e., the adhesive  800 , can be suppressed to a low level. 
     As shown in  FIG.  10   , the leading end face  461   a  of the projection  461  of the rib  460  is close to the inner peripheral side face  532   b  of the groove part  532 . When the case  500  is exposed to a high temperature, the case  500  is likely to be deformed such that the opening part  506  is expanded. In particular, this deformation is likely to occur in a center portion in the longitudinal direction (left-right direction) of the case  500 . When such a deformation of the case  500  has occurred, the inner peripheral side face  532   b  of the groove part  532  comes into contact with the leading end face  461   a  of the projection  461 . Accordingly, deformation of the case  500  is suppressed. It should be noted that, in a state before the case  500  has been deformed, the leading end face  461   a  of the projection  461  may be in contact with the inner peripheral side face  532   b  of the groove part  532 . 
     When the electrical storage module  1  is mounted to an external apparatus provided in an automobile or the like, the rear side face part  503  side of the case  500  is fixed to a fixation part of the external apparatus by screwing at the mounting bosses  510 . Then, a connector (not shown) provided to the external apparatus is connected to the connector  600  of the electrical storage module  1 . When assistance, backup, or the like of power becomes necessary on the external apparatus side, power outputted from the five electrical storage devices  100  is supplied to the external apparatus through the connector  600  and the connector of the external apparatus. 
     When temperature rise has occurred in the case  500  due to heat generation or the like of the electrical storage device  100  during use, air in the case  500  expands. At this time, the expanded air passes through the ventilation membrane  424  to be released from the ventilation hole  421  to the outside. Therefore, rising of the internal pressure of the case  500  can be prevented. Meanwhile, even when water has entered from the ventilation hole  421 , the water cannot pass through the ventilation membrane  424 . Therefore, entry of water into the case  500  is prevented. 
     Effect of Embodiment 
     The electrical storage module  1  of the present embodiment has been described above. According to the electrical storage module  1  of the present embodiment, the following effects can be exhibited. 
     The electrical storage module  1  is configured such that: the case  500  includes the groove part  532  at the outer periphery of the opening part  506 ; the lid  400  includes the rib  460  to be inserted into the groove part  532 ; and the sealing member  800  is present between the rib  460  and the groove part  532 . 
     According to this configuration, as shown in  FIG.  9 A , the rib  460  can be pushed into the sealing member (adhesive)  800 , and the sealing member  800  can be deformed to enter between the rib  460  and the outer peripheral side face  532   c  of the groove part  532 , and enter between the rib  460  and the inner peripheral side face  532   b  of the groove part  532 . Accordingly, the seal length L of the sealing member  800  can be made long, and thus, the waterproofing effect between the lid  400  and the case  500  by the sealing member  800  can be expected to be enhanced. 
     The sealing member (adhesive)  800  has a characteristic in which a state where the viscosity of the sealing member (adhesive)  800  is low changes to a state where the viscosity is high. Therefore, when the rib  460  is inserted into the groove part  532  in a state where the viscosity of the sealing member  800  is low, and the rib  460  is pushed into the sealing member  800 , the sealing member  800  can be easily deformed. Therefore, the seal length L of the sealing member  800  can be easily made long. 
     Further, since the sealing member  800  is an adhesive, the lid  400  and the case  500  can be adhered to each other. Therefore, the lid  400  and the case  500  can be fixed to each other by a small number of screws  700 . 
     Further, the case  500  includes the inner peripheral upper face  531   a  and the outer peripheral upper face  531   b  respectively on the inner side and the outer side of the groove part  532 , and the position of the inner peripheral upper face  531   a  is lower than the position of the outer peripheral upper face  531   b . 
     According to this configuration, as shown in  FIG.  9 A , the groove part  532  is shallow on the inner peripheral upper face  531   a  side, and the sealing member (adhesive)  800  becomes able to enter between the inner peripheral bottom face  402   a  of the lid  400  and the inner peripheral upper face  531   a . Since the sealing member  800  is present also between the inner peripheral bottom face  402   a  of the lid  400  and the inner peripheral upper face  531   a , the seal length L of the sealing member  800  can be made even longer, and the waterproofing effect can be further enhanced. 
     Further, the lid  400  includes, on the inner side of the rib  460 , the outer peripheral rib  451  to be inserted inside the case  500 , and a gap is formed between the inner peripheral wall face  507  of the case  500  and the outer peripheral rib  451 . 
     According to this configuration, as shown in  FIG.  9 B , the sealing member (adhesive)  800  can be caused to enter also between the outer peripheral rib  451  and the inner peripheral wall face  507  of the case  500 , whereby the seal length L of the sealing member  800  can be made even longer. 
     Further, the distance D1 between the inner peripheral wall face  507  of the case  500  and the outer peripheral rib  451  of the lid  400  which form a gap is smaller than the distance D2 between the leading end of the rib  460  and the bottom face  532   a  of the groove part  532 . Therefore, increase in the amount of the sealing member  800  can be suppressed to a low level. 
     Further, as shown in  FIG.  10   , the lid  400  includes the leading end face  461   a  of the projection  461  facing, at the rib  460 , the inner side. The case  500  includes the inner peripheral side face  532   b , of the groove part  532 , that is close to the leading end face  461   a . 
     According to this configuration, when deformation of the case  500  so as to expand the opening part  506  has occurred, the inner peripheral side face  532   b  of the groove part  532  comes into contact with the leading end face  461   a  of the projection  461 . Accordingly, deformation of the case  500  can be suppressed. 
     Further, as shown in  FIG.  9 A , the outer peripheral bottom face  402   b  of the lid  400  is in contact with the outer peripheral upper face  531   b  of the case  500 . Therefore, water is less likely to enter up to the groove part  532  from outside. In addition, the corner portion between the outer peripheral upper face  531   b  of the case  500  and the outer peripheral side face  532   c  of the groove part  532  is in an angular state. Therefore, at an entrance portion to the groove part  532 , a gap is less likely to occur between the outer peripheral upper face  531   b  of the case  500  and the outer peripheral bottom face  402   b  of the lid  400 , and water is further less likely to enter up to the groove part  532  from the outside. 
     Further, the case  500  includes, on the outer peripheral side with respect to the opening part  506 , the bosses  535 ,  536  including the screw holes  534   a ,  534   d  to which the screws  700  are fastened, and the lid  400  includes the mounting holes  411 ,  414  in which the bosses  535 ,  536  are fitted. 
     According to this configuration, when the bosses  535 ,  536  are fitted in the mounting holes  411 ,  414 , the lid  400  is positioned in the in-plane direction (front-rear and left-right directions) of the opening face of the opening part  506 , with respect to the case  500 . Accordingly, the lid  400  can be accurately fixed to the case  500 . 
     Further, since the bottom face  532   a  of the groove part  532  is a face having been subjected to the emboss processing  533 , the lid  400  and the case  500  can be more easily adhered by the adhesive  800 . 
     Further, since the inner peripheral side face  532   b  and the outer peripheral side face  532   c  of the groove part  532  are also faces having been subjected to the emboss processing  533 , the lid  400  and the case  500  are further more easily adhered by the adhesive  800 . In addition, the portion of the emboss processing  533  can be used as a mark when the adhesive  800  is loaded into the groove part  532 . 
     Although an embodiment of the present invention has been described, the present invention is not limited to the above embodiment. In addition, application examples of the present invention can also be modified in various ways, in addition to the above embodiment. 
     For example, in the above embodiment, the sealing member  800  is implemented by the cured adhesive  800 . However, the sealing member  800  may be implemented by any material as long as the material can be deformed when the rib  460  is pushed thereinto. For example, the sealing member  800  may be implemented by an ultraviolet curing resin that has viscosity and that is cured by application of ultraviolet light. Alternatively, the sealing member  800  may be implemented by an elastic material such as a rubber having a high flexibility. 
     In the above embodiment, the lid attachment part  530  of the case  500  is configured such that the position of the inner peripheral upper face  531   a  is lower than the position of the outer peripheral upper face  531   b . However, as shown in  FIG.  11 A , the lid attachment part  530  may be configured such that the position of the outer peripheral upper face  531   b  is lower than the position of the inner peripheral upper face  531   a . In this case, the sealing member  800  is present not only between the rib  460  and the groove part  532  but also between the outer peripheral upper face  531   b  and the outer peripheral bottom face  402   b  of the lid  400 . When such a configuration is adopted as well, the seal length L of the sealing member  800  can be made long. 
     Further, in the above embodiment, after the adhesive  800  has been disposed (injected) in the groove part  532  of the lid attachment part  530 , the rib  460  of the lid  400  is inserted into the groove part  532 . However, after the adhesive  800  has been disposed (applied) at the rib  460  of the lid  400 , the rib  460  may be inserted into the groove part  532 . 
     Further, in the above embodiment, the projection  461  is formed in the rib  460  of the lid  400 . However, as shown in  FIG.  11 B , a projection  540  projecting to the rib  460  side may be provided to the inner peripheral side face  532   b  of the groove part  532  of the case  500 , and a leading end face  540   a  of the projection  540  may be close to a side face  460   a  on the inner side of the rib  460 . Further, the leading end face  540   a  of the projection  540  and the side face  460   a  of the rib  460  may be in contact with each other. When such a configuration is adopted as well, deformation of the case  500  so as to expand the opening part  506  can be suppressed. It should be noted that the side face  460   a  corresponds to “fourth face part” described in the claims, and the leading end face  540   a  corresponds to “fifth face part” described in the claims. 
     Further, the projection  461  of the rib  460  or the projection  540  of the groove part  532  may be provided not only to the center portion in the longitudinal direction of the lid  400  or the case  500 , but also to another place. 
     Further, in the above embodiment, with respect to the lid attachment part  530  of the case  500 , the corner portion between the outer peripheral side face  532   c  of the groove part  532  and the outer peripheral upper face  531   b  is not chamfered, and is angular. However, as shown in  FIG.  12 A , at the corner portion between the outer peripheral side face  532   c  of the groove part  532  and the outer peripheral upper face  531   b , an R-chamfer  538  of which the chamfer amount is smaller than that of an R-chamfer  532   d  formed at the corner portion between the bottom face  532   a  and the outer peripheral side face  532   c  of the groove part  532 , may be formed, or alternatively, as shown in  FIG.  12 B , a C-chamfer  539  of which the chamfer amount is smaller than that of the R-chamfer  532   d  may be formed. When these configurations are adopted as well, water is less likely to enter up to the groove part  532  although the effect is reduced when compared with that in the above embodiment. 
     Further, in the above embodiment, in the lid attachment part  530 , the bosses  535 ,  536  are provided at two corner portions that are in a diagonal relationship. However, bosses may be provided at two corner portions that are at the same position in the left-right direction, or two corner portions that are at the same position in the front-rear direction. Alternatively, bosses may be provided at three or all corner portions. Further, a boss not being a round columnar shape but being in a polygonal columnar shape, such as a quadrangular column, may be provided at one or a plurality of corner portions. In accordance with the above change of the boss, the size and shape of the mounting holes  411  to  414  of the lid  400  are changed. 
     Further, in the above embodiment, with respect to the lid  400  and the case  500 , around the outer periphery of the opening part  506 , the rib  460  and the groove part  532  between which the sealing member  800  is present are provided in one loop. However, around the outer periphery of the opening part  506 , the rib  460  and the groove part  532  between which the sealing member  800  is present may be provided in two or more loops. 
     Further, in the above embodiment, the lid  400  is formed in a plate shape. However, the lid  400  may be formed in a box shape of which the lower face is open. In this case, the rib  460  may be formed at the lower end face of the side face part of the lid  400 . Alternatively, a flange part may be provided at the lower end of the side face part of the lid  400 , and the rib  460  may be formed at the lower face of this flange part. 
     Further, in the above embodiment, five electrical storage devices  100  are used in the electrical storage module  1 . However, not limited thereto, a different number of electrical storage devices  100  may be used in the electrical storage module  1 . 
     Further, in the above embodiment, an electric double layer capacitor is used as the electrical storage device  100 . However, as the electrical storage device  100 , instead of a capacitor, a lithium ion secondary battery of which the active material of the positive electrode is a lithium transition metal oxide such as lithium cobalt oxide and the active material of the negative electrode is a carbon material may be used, for example. Further, the electrical storage device  100  need not be such a nonaqueous electrolyte secondary battery, but may be a secondary battery other than the nonaqueous electrolyte secondary battery, or may be a primary battery. 
     In addition to the above, various modifications can be made as appropriate to the embodiment of the present invention without departing from the scope of the technical idea defined by the claims. 
     In the description of the embodiments above, the terms that indicate directions such as “upper” and “lower” are relative directions that are dependent only on the relative positional relationship between component members, and do not indicate absolute directions such as the vertical direction and the horizontal direction. 
     Industrial Applicability 
     The present invention is useful for an electrical storage module that is used in various types of electronic apparatuses, electrical apparatuses, industrial apparatuses, electrical equipment of vehicles, and the like. 
     
       
         
           
               
             
               
                 DESCRIPTION OF THE REFERENCE CHARACTERS 
               
             
            
               
                   1  electrical storage module 
               
               
                   100  electrical storage device 
               
               
                   400  lid 
               
               
                   402   a  inner peripheral bottom face (sixth face part) 
               
               
                   402   b  outer peripheral bottom face (third face part) 
               
               
                   411 ,  414  mounting hole (fitting hole) 
               
               
                   451  outer peripheral rib (second protrusion) 
               
               
                   460  rib (first protrusion) 
               
               
                   460   a  side face (fifth face part) 
               
               
                   461   a  leading end face (fourth face part) 
               
               
                   500  case 
               
               
                   531   a  inner peripheral upper face (first face part) 
               
               
                   531   b  outer peripheral upper face (second face part) 
               
               
                   532  groove part (recess) 
               
               
                   532   a  bottom face 
               
               
                   532  groove part (recess) 
               
               
                   532   a  bottom face 
               
               
                   532   b  inner peripheral side face (fifth face part, side face) 
               
               
                   532   c  outer peripheral side face (side face) 
               
               
                   532   d  R-chamfer 
               
               
                   533  emboss processing (surface roughening processing) 
               
               
                   535 ,  536  boss 
               
               
                   538  R-chamfer 
               
               
                   539  C-chamfer 
               
               
                   540   a  leading end face (fourth face part) 
               
               
                   506  opening part 
               
               
                   507  inner peripheral wall face (inner wall face) 
               
               
                   700  screw 
               
               
                   800  adhesive, sealing member 
               
               
                 D1 distance 
               
               
                 D2 distance