Patent Publication Number: US-2023137433-A1

Title: Electrical storage module

Description:
TECHNICAL FIELD 
     The present disclosure relates to an electrical storage module. 
     BACKGROUND ART 
     It is known to use an electrical storage module in which a plurality of electrical storage devices are electrically connected by a bus bar in order to obtain a predetermined energy capacity. For example, an electrical storage module disclosed in PTL 1 includes a bus bar that connects electrode terminals of a plurality of electrical storage devices, and the bus bar is joined to the electrode terminal by welding when the bus bar is attached to the electrode terminal. Citation List Patent Literature 
     PTL 1: Unexamined Japanese Patent Publication No. 2010-161075 
     SUMMARY OF THE INVENTION 
     Technical Problem 
     However, if the bus bar is joined by welding when attached to the electrode terminal in the electrical storage module, it is difficult to disassemble the electrical storage device and the bus bar and reassemble the electrical storage module in the process of manufacturing the electrical storage module. 
     An object of the present disclosure is to provide an electrical storage module that can be reassembled. 
     Solution to Problem 
     An electrical storage module that is one aspect of the present disclosure is an electrical storage module including: a plurality of electrical storage devices; and a bus bar that connects electrode terminals of the electrical storage devices to each other, in which the electrical storage device includes an outer covering can in which an opening is formed, and a plate-shaped sealing body that is provided with the electrode terminal and is inserted into the opening of the outer covering can, the electrode terminal has a container that includes a through-hole or a recess that is formed in a direction substantially orthogonal to a direction in which the sealing body is inserted into the outer covering can, and the bus bar includes a press-fitting portion that is press-fitted into the container when attached to the electrode terminal. 
     Advantageous Effect of Invention 
     According to one aspect of the present disclosure, it becomes easy to remove a bus bar from an electrode terminal as compared with an electrical storage module in which the bus bar and the electrode terminal are joined to each other by welding. By press-fitting the press-fitting portion of the bus bar into the electrode terminal, it is possible to reduce connection resistance between the bus bar and the electrode terminal. Furthermore, by making the direction in which the press-fitting portion is press-fitted into the container of the electrode terminal different from the direction in which the sealing body is inserted into the outer covering can, it is possible to suppress mechanical stress generated at a joint between the sealing body and a case when the press-fitting portion is press-fitted into the container. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an electrical storage module that is an example of an exemplary embodiment. 
         FIG.  2    is an AA cross-sectional view of  FIG.  1   . 
         FIG.  3    is a perspective view of an electrode terminal that is an example of an exemplary embodiment. 
         FIG.  4    is a CC cross-sectional view of  FIG.  3   . 
         FIG.  5    is a perspective view of a bus bar that is an example of an exemplary embodiment. 
         FIG.  6    is a BB cross-sectional view of  FIG.  1   . 
         FIG.  7    is a perspective view of a fixing member that is an example of an exemplary embodiment. 
         FIG.  8    is a cross-sectional view that is another example of an exemplary embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     Hereinafter, an exemplary embodiment of the present disclosure will be described with reference to the drawings. The shapes, materials, and numbers described below are examples, and can be appropriately changed according to the specifications of the electrical storage module. In the following description, the equivalent elements are given the identical reference marks in all drawings. 
     Hereinafter, for convenience of description, a direction in which the sealing body is inserted into the opening of the outer covering can is defined as a vertical direction, a direction substantially orthogonal to the vertical direction and in which a storage of the electrode terminal is formed is defined as a width direction, and a direction substantially orthogonal to the vertical direction and the width direction and in which the electrical storage devices are arranged in the electrical storage module is defined as a depth direction. 
     Electrical storage module  10 , which is an example of an exemplary embodiment, will be described with reference to  FIG.  1   .  FIG.  1    is a perspective view showing electrical storage module  10 . 
     Electrical storage module  10  is used in, for example, a driving power source of an electric vehicle or a hybrid vehicle, or a stationary electrical storage system for peak shifting of system power. As shown in  FIG.  1   , electrical storage module  10  includes: a plurality of electrical storage devices  20  arranged side by side in a depth direction; bus bar  40  connecting positive-electrode terminals  31  or negative-electrode terminals  32  (see  FIG.  2   ) of electrical storage devices  20  to each other; and fixing member  50  connecting positive-electrode terminal  31  and bus bar  40  or negative-electrode terminal  32  and bus bar  40  to each other. 
     Electrical storage device  20 , which is an example of the exemplary embodiment, will be described with reference to  FIG.  2   .  FIG.  2    is an AA cross-sectional view of  FIG.  1   . 
     Electrical storage device  20  is a non-aqueous electrolyte secondary battery, and a preferred example thereof is a lithium ion battery. Electrical storage device  20  may be a nickel hydride battery, an electric double layer capacitor, or the like. As shown in  FIG.  2   , electrical storage device  20  includes: electrode body  21  in which a positive electrode plate and a negative electrode plate are laminated via a separator; outer covering can  22  in which electrode body  21  and an electrolyte solution are contained; and sealing body  23  in which opening  22 A of outer covering can  22  is inserted from above in the vertical direction to close the opening. 
     Electrode body  21  is formed by laminating a substantially rectangular sheet-like positive electrode plate, a negative electrode plate, and a separator. The laminated positive electrode plate, the negative electrode plate, and the separator may be fixed by bonding the positive electrode plate or the negative electrode plate to the separator by applying an adhesive to a surface of the separator opposing the positive electrode plate or the negative electrode plate, which is restrained using a fixing tape. Electrode body  21  is contained in insulating holder  24  in a substantially rectangular-parallelepiped shape having a bottom and having an upper end opened. Electrode body  21  is disposed in outer covering can  22  such that a lamination direction in which the positive electrode plate and the negative electrode plate are laminated is parallel to the depth direction of outer covering can  22 . In electrode body  21 , a band-shaped positive electrode plate and a band-shaped negative electrode plate may be wound via a band-shaped separator to form a wound body, and the wound body may be flattened to form a flat wound body. At this time, the lamination direction of electrode body  21  may be a thickness direction of the flat wound body. 
     The positive electrode plate includes, for example, a core body made of an aluminum foil having a thickness of 15 µm, electrode layers formed on front and back surfaces of the core body, a core body exposed part where no electrode layer is formed in the core body, and positive electrode lead  25 , which is a part of the core body exposed part and is formed to extend from an upper end of the core body exposed part. 
     The electrode layer of the positive electrode contains, for example, an active material, a conductive agent, and a binder. Lithium-nickel-cobalt-manganese composite oxide can be used as an active material of the positive electrode, polyvinylidene fluoride (PVdF) can be used as a binder, a carbon material can be used as a conductive agent, and N-methylpyrrolidone (NMP) can be used as a dispersion medium. When forming the electrode layer, a slurry containing the active material, the conductive agent, the binder, and the dispersant is prepared. The slurry is applied on both surfaces of the core body of the positive electrode. Then, by drying, the dispersion medium in the slurry is removed, and an electrode layer is formed on the core body. Thereafter, the electrode layer is compressed to have a predetermined thickness. The thus obtained positive electrode plate is cut into a predetermined shape. 
     The negative electrode plate includes, for example, a core body made of a copper foil having a thickness of 8 µm, electrode layers formed on front and back surfaces of the core body, a core body exposed part where no electrode layer is formed in the core body, and negative electrode lead  26 , which is a part of the core body exposed part and is formed to extend from an upper end of the core body exposed part. 
     The electrode layer of the negative electrode contains, for example, an active material, a conductive agent, a binder, and a thickener. Graphite can be used as an active material of the negative electrode, styrene butadiene rubber (SBR) can be used as a binder, carboxymethyl cellulose (CMC) can be used as a thickener, and water can be used as a dispersion medium. When forming the electrode layer, a slurry containing the active material, the conductive agent, the binder, and the thickener is prepared. The slurry is applied on both surfaces of the core body of the negative electrode. Then, by drying, the dispersion medium in the slurry is removed, and an electrode layer is formed on the core body. Thereafter, the electrode layer is compressed to have a predetermined thickness. The thus obtained negative electrode plate is cut into a predetermined shape. 
     For example, a resin separator can be used as the separator, and polyolefin, polyethylene, or polypropylene can be used as the resin. 
     Positive electrode lead  25  is electrically connected to positive-electrode terminal  31  provided on sealing body  23  via current collecting member  27 . Positive electrode lead  25  is provided by the number of positive electrode plates constituting electrode body  21 . The plurality of positive electrode leads  25  are each joined to current collecting member  27  in a bundled state near the tip end in the extending direction. When positive electrode lead  25  is joined to current collecting member  27 , positive electrode lead  25  can be joined to current collecting member  27  by performing ultrasonic welding, resistance welding, laser welding, cold welding, or the like. 
     Negative electrode lead  26  is electrically connected to negative-electrode terminal  32  provided on sealing body  23  via current collecting member  28 . Negative electrode lead  26  is provided by the number of negative electrode plates constituting electrode body  21 . The plurality of negative electrode leads  26  are each joined to current collecting member  28  in a bundled state near the tip end in the extending direction. When negative electrode lead  26  is each joined to current collecting member  28 , negative electrode lead  26  can be joined to current collecting member  28  by performing ultrasonic welding, resistance welding, laser welding, cold welding, or the like. 
     Current collecting member  27  of the positive electrode is made of, for example, an aluminum plate material. Current collecting member  27  is connected to positive electrode lead  25  at one end and is connected to positive-electrode terminal  31  at the other end. Insulating member  33  is interposed between current collecting member  27  and sealing body  23 . 
     Positive-electrode terminal  31  and current collecting member  27  may be electrically connected via a current interrupting device (CID). The CID is a safety device capable of cutting off electrical connection between current collecting member  27  and positive-electrode terminal  31  when gas is generated inside outer covering can  22  at the time of abnormality of electrical storage device  20  and the inside of outer covering can  22  exceeds a predetermined pressure. The CID includes, for example, a reversing plate that is connected to the other end of current collecting member  27  and deforms in a direction away from current collecting member  27  when receiving pressure in outer covering can  22 , and a conductive cap that electrically connects the reversing plate and positive-electrode terminal  31 . The conductive cap is a dish-shaped conductive member having an opening positioned on the lower side (electrode body  21  side) and an upper surface positioned on the upper side (sealing body  23  side). A connection hole is formed on the upper surface, and positive-electrode terminal  31  is inserted. 
     Current collecting member  28  of the negative electrode is made of, for example, a copper plate material. Current collecting member  28  is connected to negative electrode lead  26  at one end and connected to negative-electrode terminal  32  at the other end. Insulating member  34  is interposed between current collecting member  28  and sealing body  23 . 
     Exterior can  22  is, for example, a rectangular case provided with bottom  22 B, a side wall having a rectangular tube shape erected from a peripheral edge of bottom  22 B, and opening  22 A at an end opposite to bottom  22 B (upper side in the vertical direction). Exterior can  22  is made of metal, for example, aluminum. Exterior can  22  can be formed by, for example, drawing an aluminum material. 
     In sealing body  23 , positive-electrode terminal  31  and negative-electrode terminal  32  are disposed apart from each other in a long direction (width direction) of sealing body  23 . Positive-electrode terminal  31  and negative-electrode terminal  32  are provided to protrude upward in the vertical direction and protrude from the top surface of sealing body  23 . Sealing body  23  is formed by, for example, processing an aluminum plate. Sealing body  23  is positioned on opening  22 A of outer covering can  22 , and sealing body  23  can seal the inside of outer covering can  22  by forming a joint by welding an opening end of outer covering can  22  using, for example, a laser or the like. 
     Sealing body  23  may have a filling hole for filling an electrolyte solution into outer covering can  22 . Sealing body  23  may be provided with a filling plug that closes the filling hole. Sealing body  23  may be surrounded by a plurality of linear grooves, and may be provided with pressure regulating valve  36  that discharges the gas inside outer covering can  22  to the outside by tearing the grooves when the inside of outer covering can  22  exceeds a predetermined pressure. It is preferable to form an annular groove along the peripheral edge on the top surface of sealing body  23 . This configuration makes it possible to efficiently melt the peripheral edge of sealing body  23  when sealing body  23  and opening  22 A of outer covering can  22  are joined by welding. 
     Positive-electrode terminal  31  is provided to penetrate a terminal hole of sealing body  23 , and has one end protruding to the outside of outer covering can  22  and the other end contained in outer covering can  22 . Positive-electrode terminal  31  is fixed to the conductive cap by having the other end inserted into a connection hole provided on the upper surface of the conductive cap, and the other end crimped so as to expand in a radial direction. Positive-electrode terminal  31  includes, for example, a columnar body or a cylindrical body made of aluminum. 
     Negative-electrode terminal  32  is provided to penetrate a terminal hole of sealing body  23 , and has one end exposed to the outside of outer covering can  22  and the other end contained in outer covering can  22 . Negative-electrode terminal  32  may include, for example, a clad material in which the other end connected to current collecting member  28  in outer covering can  22  is made of a copper material and one end exposed to the outside of outer covering can  22  is made of aluminum. Negative-electrode terminal  32  is fixed to sealing body  23  together with current collecting member  28  by being crimped so as to spread in the radial direction at the other end. 
     Hereinafter, when a feature common to positive-electrode terminal  31  and negative-electrode terminal  32  is described, it is simply described as electrode terminal  30 . 
     Electrode terminal  30 , which is an example of the present exemplary embodiment, will be described with reference to  FIGS.  3  to  5   .  FIG.  3    is a perspective view showing electrode terminal  30 , and  FIG.  4    is a CC cross-sectional view of  FIG.  3   . 
     As shown in  FIG.  3   , electrode terminal  30  is provided to protrude upward in the vertical direction of electrical storage device  20 . Electrode terminal  30  has container  30 A including a through-hole and a recess formed in the width direction. As shown in  FIG.  4   , the cross-sectional shape perpendicular to the direction in which container  30 A extends (in the width direction of the electrical storage device, in a direction of connecting the opening and the bottom of the container in a case of a bottomed container, or in a direction of connecting openings at both ends in a case where the container is a through-hole) may be rectangular. The cross-sectional shape of container  30 A perpendicular to the vertical direction may be rectangular. The cross-sectional shape of container  30 A perpendicular to the vertical direction may be formed such that the opening end on the outside in the width direction (insertion side of press-fitting portion  40 A) is wide. Thus, press-fitting portion  40 A can be easily press-fitted. The cross-sectional shape of container  30 A perpendicular to the vertical direction may be a tapered shape, and may be, for example, a trapezoid or a triangle. 
     As shown in  FIG.  5   , electrode terminal  30  includes, for example, base  30 B formed in a flat plate shape and terminal portion  30 C formed in a cylindrical shape. As a method of manufacturing electrode terminal  30 , a recess or the like may be formed on a bottom surface of terminal portion  30 C by cutting or casting, for example, the bottom surface of terminal portion  30 C and base  30 B may be joined by welding, and a recess or a through-hole defined by the recess and base  30 B as container  30 A. Electrode terminal  30  facilitates processing of forming container  30 A in terminal portion  30 C. The welding is preferably performed by spot welding at a plurality of locations, for example. In electrode terminal  30 , container  30 A may be formed by cutting or the like a conductive member in which terminal portion  30 C and base  30 B are integrated. A lower flange (not illustrated) may be formed on an outer peripheral surface of terminal portion  30 C near base  30 B, and the lower flange and base  30 B may be joined by welding or the like. 
     Bus bar  40 , which is an example of the present exemplary embodiment, will be described with reference to  FIGS.  5  and  6   .  FIG.  5    is a perspective view showing bus bar  40 .  FIG.  6    is a BB cross-sectional view of  FIG.  1   . 
     Bus bar  40  is a conductor used for electrical connection between positive-electrode terminals  31  or negative-electrode terminals  32 . As shown in  FIG.  5   , bus bar  40  is formed by bending a long metal sheet having conductivity. Bus bar  40  is detachable from electrode terminal  30  from the outside in the width direction of the plurality of electrical storage devices  20 . Bus bar  40  includes press-fitting portion  40 A press-fitted into container  30 A of electrode terminal  30 , and connecting portion  40 B that connects adjacent press-fitting portions  40 A to each other. 
     As shown in  FIG.  5   , before bus bar  40  is attached to electrode terminal  30  (before press-fitting portion  40 A is press-fitted into container  30 A), press-fitting portion  40 A may be formed by folding back a metal sheet forming press-fitting portion  40 A so as to have a substantially V shape when viewed in the vertical direction. When bus bar  40  is attached to electrode terminal  30 , press-fitting portion  40 A is press-fitted toward inside container  30 A. 
     Press-fitting is to push press-fitting portion  40 A toward container  30 A with more than or equal to a predetermined pressure in the width direction. In order to press-fit press-fitting portion  40 A into container  30 A, it is preferable that the size of press-fitting portion  40 A in the depth direction before press-fitting is larger than the size of container  30 A in the depth direction. Press-fitting portion  40 A press-fitted into container  30 A is held between a pair of inner surfaces opposing each other in the depth direction in container  30 A. At this time, a reaction force acts on the pair of inner surfaces of the pair of metal sheets constituting the press-fitting portion due to flexibility (or, elasticity or spring property) in the depth direction. Due to this, press-fitting portion  40 A and the pair of inner surfaces of container  30 A press each other. Therefore, the connection resistance between press-fitting portion  40 A and container  30 A is reduced. 
     Due to this, when bus bar  40  is attached to electrode terminal  30 , although more than or equal to a predetermined load acts in the width direction by press-fitting, the load is suppressed from acting in the vertical direction (direction in which sealing body  23  is inserted into outer covering can  22 ). Therefore, it is possible to suppress application of mechanical stress to the joint due to welding between outer covering can  22  and sealing body  23 . 
     Since bus bar  40  is detachable from electrode terminal  30 , it is possible to redo the work of attaching bus bar  40  to electrode terminal  30  in the manufacturing process of electrical storage module  10 . Furthermore, bus bar  40  can be reused at the time of disposal of electrical storage module  10 . 
     Connecting portion  40 B is a portion that connects adjacent press-fitting portions  40 A to each other as described above. The part of connecting portion  40 B close to press-fitting portion  40 A is provided with hole  40 C into which insertion portion  50 B of fixing member  50  is inserted. Hole  40 C is preferably formed in a rectangular shape. 
     As shown in  FIG.  6   , after bus bar  40  is attached to electrode terminal  30  (after press-fitting portion  40 A is press-fitted into container  30 A), the metal sheets forming press-fitting portion  40 A are press-fitted into container  30 A in a closed state. In this state, the metal sheet forming press-fitting portion  40 A and the inner surface of container  30 A opposing the metal sheet reliably abut on each other due to restoring force of returning the metal sheets forming press-fitting portion  40 A from the closed state to the V shape. This makes it possible to sufficiently secure a contact area between container  30 A and press-fitting portion  40 A. 
     The size of press-fitting portion  40 A in the width direction is not particularly limited, but is preferably substantially identical to the diameter of terminal portion  30 C of electrode terminal  30 . The size of press-fitting portion  40 A in the vertical direction is preferably smaller than the size of container  30 A of electrode terminal  30  in the vertical direction. 
     Fixing member  50 , which is an example of the present exemplary embodiment, will be described with reference to  FIGS.  6  and  7   .  FIG.  7    is a perspective view showing fixing member  50 . 
     Fixing member  50  is a member that fixes electrode terminal  30  and bus bar  40 . According to fixing member  50 , it is possible to prevent bus bar  40  from falling off from electrode terminal  30 . Fixing member  50  may be made of an insulating material having elasticity (or flexibility) or may be made of a metal material. As shown in  FIGS.  6  and  7   , fixing member  50  includes fitting portion  50 A fitted to the side peripheral surface of terminal portion  30 C of electrode terminal  30 , and insertion portion  50 B to be inserted into hole  40 C formed in bus bar  40 . 
     Fitting portion  50 A is a band-shaped member curved so as to be formed in a substantially annular shape when viewed in the vertical direction, for example. The substantially annular diameter of fitting portion  50 A as viewed in the vertical direction is preferably smaller than the diameter of electrode terminal  30 . When fixing member  50  is attached to electrode terminal  30 , fitting portion  50 A is preferably fitted to terminal portion  30 C from above. Fitting portion  50 A preferably abuts on substantially the entire circumference of the side peripheral surface of terminal portion  30 C, but may have a configuration of abutting on only a part of the side peripheral surface of terminal portion  30 C. In this case, fitting portion  50 A is formed in, for example, a substantially U shape when viewed in the vertical direction. Instead of band-shaped fitting portion  50 A as shown in  FIGS.  6  and  7   , a recess formed by cutting out a part of the peripheral edge of a block body may be adopted. At this time, fitting portion  50 A does not have flexibility or elasticity, and may be firmly fixed by making the inner dimension of a cavity defined by fitting portion  50 A and bus bar  40  at the time of connecting and fixing fixing member  50  and bus bar  40  smaller than the outer dimension of the electrode terminal. Even if fitting portion  50 A has a band shape, it may be fixed by a difference between the inner dimension of the cavity and the outer dimension of the terminal of the electrode. When fixing member  50  is used, a flange may be provided at a position above fitting portion  50 A on the outer peripheral surface of electrode terminal  30 , and this flange may overlap fitting portion  50 A when viewed from above the electrical storage device. With this configuration, fitting portion  50 A is disposed between this flange and base  30 B of electrode terminal  30 . Therefore, vertical displacement of fitting portion  50 A by the electrode terminal can be suppressed. Then, it is possible to suppress vertical displacement of bus bar  40  via fixing member  50 . 
     Insertion portion  50 B is formed on an outer end surface of fixing member  50  in the width direction. Insertion portion  50 B includes an upper insertion portion formed on the upper side in the vertical direction and a lower insertion portion formed on the lower side in the vertical direction. The upper insertion portion and the lower insertion portion are formed at a gap to each other. The upper insertion portion has upper locking portion  50 C formed so as to protrude upward near the tip end of the upper insertion portion. The lower insertion portion has lower locking portion  50 D formed so as to protrude downward near the tip end of the lower insertion portion. Note that insertion portion  50 B may be only one of the upper insertion portion and the lower insertion portion as long as the connection strength is maintained. 
     When fixing member  50  is attached to bus bar  40 , insertion portion  50 B is inserted into hole  40 C of bus bar  40 , and upper locking portion  50 C and lower locking portion  50 D are each locked to an outer opening edge portion of hole  40 C in the width direction, thereby fixing fixing member  50  to bus bar  40 . This makes it possible to suppress displacement of bus bar  40  in the width direction (direction in which container  30 A extends) when electrode terminal  30  and bus bar  40  are fixed to each other by fixing member  50  and, in particular, when electrical storage module  10  is vibrated. Then, it is possible to suppress bus bar  40  from falling off from electrode terminal  30 . 
     As shown in  FIG.  8   , in a case where container  30 A includes a through-hole, connection may be performed using a pair of bus bars  40  with respect to one electrode terminal  30 . In this case, press-fitting portion  40 A of each bus bar  40  may be inserted from the openings at both ends of container  30 A. This configuration makes it possible to reduce the press-fitting depth of one bus bar in a case where the total press-fitting depth is the same, as compared with a configuration in which one bus bar is used for one electrode terminal  30 . Therefore, the area of press-fitting portion  40 A of one bus bar  40  in contact with container  30 A is reduced. Therefore, frictional resistance at one place of press-fitting portion  40 A is reduced, and the burden of work due to one press fitting of bus bar  40  can be reduced. As shown in  FIG.  8   , connecting portions  40 B of the pair of bus bars  40  may be bundled together by a restraining member or the like. This configuration makes it possible to suppress bus bar  40  fixed to electrode terminal  30  from displacing in the width direction. 
     According to electrical storage module  10 , by press-fitting press-fitting portion  40 A of bus bar  40  into container  30 A of electrode terminal  30  in the width direction, it is possible to suppress the load from acting in the vertical direction (direction in which sealing body  23  is inserted into outer covering can  22 ). Therefore, it is possible to suppress the mechanical stress generated at the joint between outer covering can  22  and sealing body  23 . 
     According to electrical storage module  10 , since press-fitting portion  40 A is press-fitted into container  30 A, the metal sheet forming press-fitting portion  40 A and the inner surface of container  30 A opposing the metal sheet reliably abut on each other. This makes it possible to sufficiently secure a contact area between container  30 A and press-fitting portion  40 A. As a result, the contact resistance between container  30 A and press-fitting portion  40 A can be reduced, and the heat generation amount when a large current flow through bus bar  40  can be reduced. 
     Furthermore, according to electrical storage module  10 , electrode terminal  30  and bus bar  40  are joined to each other by fixing member  50 , and in particular, when electrical storage module  10  vibrates, it is possible to avoid bus bar  40  from falling off from electrode terminal  30 . 
     Note that the present invention is not limited to the above-described exemplary embodiments and modified examples thereof, and it is a matter of course that various changes and improvements can be made within the scope of the matters described in the claims of the present application.  
     
       
         
           
               
               
             
               
                 REFERENCE MARKS IN THE DRAWINGS 
               
             
            
               
                 
                   10 
                 
                 electrical storage module 
               
               
                 
                   20 
                 
                 electrical storage device 
               
               
                 
                   21 
                 
                 electrode body 
               
               
                 
                   22 
                 
                 outer covering can 
               
               
                   22 A 
                 opening 
               
               
                   22 B 
                 bottom 
               
               
                 
                   23 
                 
                 sealing body 
               
               
                 
                   24 
                 
                 insulating holder 
               
               
                 
                   25 
                 
                 positive electrode lead 
               
               
                 
                   26 
                 
                 negative electrode lead 
               
               
                 
                   27 
                 
                 current collecting member 
               
               
                 
                   28 
                 
                 current collecting member 
               
               
                 
                   30 
                 
                 electrode terminal 
               
               
                   30 A 
                 container 
               
               
                   30 B 
                 base 
               
               
                   30 C 
                 terminal portion 
               
               
                 
                   31 
                 
                 positive-electrode terminal 
               
               
                 
                   32 
                 
                 negative-electrode terminal 
               
               
                 
                   33 
                 
                 insulating member 
               
               
                 
                   34 
                 
                 insulating member 
               
               
                 
                   36 
                 
                 pressure regulating valve 
               
               
                 
                   40 
                 
                 bus bar 
               
               
                   40 A 
                 press-fitting portion 
               
               
                   40 B 
                 connecting portion 
               
               
                   40 C 
                 hole 
               
               
                 
                   50 
                 
                 fixing member 
               
               
                   50 A 
                 fitting portion 
               
               
                   50 B 
                 insertion portion 
               
               
                   50 C 
                 upper locking portion 
               
               
                   50 D 
                 lower locking portion