JP2016122532A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit foreign materials from entering an electrode assembly.SOLUTION: When a power storage device includes an insulation cover 100 electrically insulating between a case 11 and a joint section formed between a positive electrode tab 31 projecting from an electrode assembly 14 and a positive electrode conductive member 40, and between the case 11 and a joint section formed between a negative electrode tab 32 projecting from the electrode assembly 14 and a negative electrode conductive member 60, holding tapes t1, t2 are adhered to a portion which does not overlap a cover facing region facing the insulation cover 100, on a tab side end surface 14c. Thus, by the insulation cover 100 and the holding tapes t1, t2, the tab side end surface 14c has less exposed portion.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a power storage device having an electrode assembly to which a holding tape is attached.

  A vehicle such as an EV (Electric Vehicle) or a PHV (Plug in Hybrid Vehicle) is equipped with a secondary battery such as a lithium ion battery as a power storage device that stores power supplied to an electric motor serving as a prime mover. The secondary battery includes an electrode assembly having a positive electrode and a negative electrode, a case that accommodates the electrode assembly, and electrode terminals for the positive electrode and the negative electrode. Electrically connected. A plurality of holding tapes that hold the electrode assembly in the electrode stacking direction are attached to the electrode assembly in which the sheet-like positive electrode and the negative electrode are stacked (see, for example, Patent Document 1).

JP 2013-48054 A

  A case that accommodates the electrode assembly includes a bottomed box-shaped case main body that opens in one side, and a flat lid that closes the opening of the case main body. And when accommodating an electrode assembly in a case, an electrode assembly is inserted from the opening part of a case main body, and a lid | cover is closed so that an opening part may be obstruct | occluded after that. At this time, the case is hermetically sealed by joining the case main body and the lid by welding.

  For this reason, there is a possibility that foreign matter generated during bonding or the like may remain in the case, and if the foreign matter falls due to, for example, vibration, the case may enter the electrode assembly. Foreign matter that has entered the electrode assembly can cause short-circuiting of electrodes having different polarities.

  The present invention has been made paying attention to such problems existing in the prior art, and an object of the present invention is to provide a power storage device capable of suppressing the entry of foreign matter into the electrode assembly.

  A power storage device for solving the above problems includes an electrode assembly in which electrodes of different polarities are alternately stacked in a state of being insulated from each other, a case in which the electrode assembly is accommodated, and an end of the electrode A conductive member electrically connected to the protruding tab; an electrode terminal electrically connected to the conductive member; a connecting portion between the tab and the conductive member; and an insulating cover for insulating the case; A holding tape attached from one surface to the other surface extending along a direction orthogonal to the stacking direction of the electrode assembly, and the case is joined to the case body and the case body A cover facing region facing the insulating cover on the surface of the electrode assembly facing the insulating cover, the insulating cover being located on a joint portion side of the case body and the lid. Is projected, The retaining tape portion that does not overlap with the cover facing region is located. According to this, even when the foreign matter remaining in the case is dropped when the case main body and the lid are joined, the foreign matter falls on the insulating cover or the holding tape. For this reason, it can suppress that a foreign material enters into the surface of the electrode assembly from which the tab protruded.

  In the power storage device, a terminal facing area facing the electrode terminal is projected on the surface of the electrode assembly, and at least a part of the holding tape is located in a portion overlapping the terminal facing area. preferable. According to this, it is possible to suppress entry of foreign matter from a gap or the like located directly below the electrode terminal.

  In the above power storage device, it is preferable that the holding tape is located at an end of the surface of the electrode assembly. According to this, the electrode assembly can be satisfactorily held while suppressing the entry of foreign matter by the holding tape.

  In the power storage device, the holding tape is attached to the electrode in a stacking direction, and an end portion of the holding tape along the stacking direction is located outside an end portion of the insulating cover. Preferably it is. According to this, the overlapping of the insulating cover and the holding tape can be eliminated, and the exposed portion of the surface of the electrode assembly can be efficiently covered with the holding tape.

  In the above power storage device, a preferable example of the power storage device is a secondary battery.

  According to the present invention, it is possible to suppress the entry of foreign matter into the electrode assembly.

The perspective view which shows a secondary battery. The exploded perspective view of an electrode assembly. The exploded perspective view of a secondary battery. The partial cross section figure which shows the inside of the secondary battery. The top view which shows the upper surface of an electrode assembly.

Hereinafter, an embodiment in which the power storage device is embodied as a secondary battery will be described with reference to FIGS.
As shown in FIG. 1, a secondary battery 10 as a power storage device includes a case 11. The case 11 includes a bottomed box-shaped case main body 12 that opens to one side, and a flat lid 13 that closes an opening portion of the case main body 12. The case main body 12 and the lid 13 are joined by a joining portion S. The case body 12 and the lid 13 are joined by welding.

  The case 11 has a rectangular box shape and includes a rectangular flat bottom wall 12a having a long side and a short side, and a plurality of side walls erected from the four sides of the bottom wall 12a. The bottom wall 12 a faces the lid 13 that closes the opening of the case body 12. The plurality of side walls are erected on the four sides of the bottom wall 12a with the short sides and opposed to the two short side walls 12b and 12c, and the four long sides of the bottom wall 12a are erected on the long sides and the two long side walls facing 12d, 12e. The long side walls 12d and 12e have a larger area than the short side walls 12b and 12c. The secondary battery 10 of this embodiment is a prismatic battery whose appearance is square.

  The case 11 of the secondary battery 10 contains an electrode assembly 14 and an electrolytic solution (not shown). Further, the secondary battery 10 includes a positive electrode terminal 15 and a negative electrode terminal 16 as electrode terminals. The positive electrode terminal 15 and the negative electrode terminal 16 are fastened and fixed to a lid 13 as a wall portion of the case 11. Further, the positive electrode terminal 15 and the negative electrode terminal 16 are partly located inside the case 11 and partly protrude from the case 11 to the outside. In addition, the secondary battery 10 of this embodiment is a lithium ion battery, for example.

  As shown in FIG. 2, the electrode assembly 14 has a structure in which positive electrodes 21 and negative electrodes 22 as electrodes having different polarities are alternately stacked with separators 23 interposed therebetween. The negative electrode 22 and the positive electrode 21 are insulated by a separator 23. The direction in which the positive electrode 21, the negative electrode 22, and the separator 23 are stacked is a stacking direction of the electrode assembly 14.

  The positive electrode 21, the negative electrode 22, and the separator 23 are rectangular sheets having a short side and a long side. The positive electrode 21 includes a rectangular positive metal foil (for example, an aluminum foil) 21a and positive electrode active material layers 21b on both surfaces of the positive metal foil 21a. The negative electrode 22 includes a rectangular negative metal foil (for example, copper foil) 22a and negative electrode active material layers 22b on both surfaces of the negative metal foil 22a.

  The positive electrode 21 has a positive electrode tab 31 having a shape protruding from the end 21 c of the positive electrode 21. Similarly, the negative electrode 22 has a negative electrode tab 32 having a shape protruding from the end 22 c of the negative electrode 22. The positive electrode 21 and the negative electrode 22 are laminated so that the same polarities of the tabs 31 and 32 are arranged in a row.

  As shown in FIGS. 3 and 4, the electrode assembly 14 of this embodiment is formed in a rectangular parallelepiped shape by laminating a positive electrode 21, a negative electrode 22, and a separator 23. The electrode assembly 14 has a first plane 14a and a second plane 14b facing the first plane 14a at both ends in the stacking direction. On the first plane 14a and the second plane 14b, a facing region where the positive electrode active material layer 21b and the negative electrode active material layer 22b face each other when viewed from the stacking direction is projected. The electrode assembly 14 includes a tab-side end surface 14c on one of the four surfaces surrounding the first plane 14a and the second plane 14b. The electrode assembly 14 includes a bottom surface 14d (shown in FIG. 4) on one of the four surfaces, and the bottom surface 14d faces the tab-side end surface 14c. The electrode assembly 14 includes side surfaces 14e and 14f on the remaining two surfaces of the four surfaces.

  Each surface of the electrode assembly 14 faces each wall constituting the case 11 in a state where the electrode assembly 14 is accommodated in the case 11. Specifically, the first plane 14 a and the second plane 14 b face the long side walls 12 d and 12 e of the case body 12. The tab side end surface 14 c faces the lid 13. The bottom surface 14 d faces the bottom wall 12 a of the case body 12. The side surfaces 14 e and 14 f face the short side walls 12 b and 12 c of the case body 12.

  As shown in FIG. 3, each negative electrode tab 32 is folded back to the other side in a state where the negative electrode tabs 32 are gathered toward one side in the stacking direction of the electrode assembly 14. Similarly, each positive electrode tab 31 is folded back to the other side in a state where the positive electrode tabs 31 are gathered toward one side in the stacking direction of the electrode assembly 14. Each positive electrode tab 31 and each negative electrode tab 32 protrude from the tab side end surface 14 c of the electrode assembly 14 and protrude from the tab side end surface 14 c of the electrode assembly 14 toward the lid 13.

  As shown in FIGS. 3 and 4, the secondary battery 10 includes a positive electrode conductive member 40 as a conductive member that electrically connects the positive electrode tab 31 and the positive electrode terminal 15. The positive electrode conductive member 40 is composed of a single metal plate (in this embodiment, an aluminum plate). The aluminum plate is preferably foil-shaped. The positive electrode conductive member 40 exists between the lid 13 of the case 11 and the electrode assembly 14, and is bonded to both the positive electrode tab 31 and the positive electrode terminal 15.

  The positive electrode conductive member 40 includes a positive electrode first joint portion 41 disposed relatively near the lid 13 and a positive electrode second joint portion 42 disposed closer to the electrode assembly 14 than the positive electrode first joint portion 41. And a curved positive third joint 43 connecting the first positive joint 41 and the second positive joint 42. In the positive electrode first joint portion 41, each positive electrode tab 31 is welded to a surface (lower surface) facing the tab side end surface 14c of the electrode assembly 14, and the positive electrode first joint portion 41 and each positive electrode tab 31 are electrically connected. It is connected. The first positive electrode joint 41 of the positive electrode conductive member 40 is a connection portion with the positive electrode tab 31.

  The positive electrode terminal 15 includes a prismatic positive electrode head portion 51 and a positive electrode shaft portion 52 that protrudes from the seating surface of the positive electrode head portion 51 and has a thread groove on the outer peripheral surface. The positive electrode shaft portion 52 protrudes out of the case 11 through a through hole 13 b provided in the lid 13. The positive electrode shaft portion 52 is inserted through an insulating O-ring 53. The positive electrode shaft portion 52 is inserted through a flanged ring 54. The flanged ring 54 has a cylindrical shape that fits into the through hole 13b.

  A nut 55 is screwed onto the positive electrode shaft portion 52 from above the flanged ring 54, and the positive electrode terminal 15 and the lid 13 are unitized. The flanged ring 54 is interposed between the positive electrode shaft portion 52 and the peripheral edge portion of the through hole 13 b of the lid 13, and between the nut 55 and the lid 13.

  The positive electrode head 51 is disposed in the case 11. A positive electrode second joint portion 42 of the positive electrode conductive member 40 is welded to the surface of the positive electrode head 51 on the electrode assembly 14 side. Thereby, the positive electrode conductive member 40 and the positive electrode terminal 15 are electrically connected.

  The secondary battery 10 includes an insulating first positive electrode insulating member 57 that covers a part of the positive electrode head portion 51, and an insulating second positive electrode insulating member 58 that is interposed between the positive electrode conductive member 40 and the electrode assembly 14. And. The first positive electrode insulating member 57 regulates contact between the lid 13 and the positive electrode head 51, and is attached to the positive electrode head 51 from the lid 13 side. The first positive electrode insulating member 57 covers a part of the seat surface and the outer peripheral surface of the positive electrode head portion 51. The second positive electrode insulating member 58 regulates contact between the positive electrode conductive member 40 and the electrode assembly 14.

  As shown in FIGS. 3 and 4, the secondary battery 10 includes a negative electrode conductive member 60 as a conductive member that electrically connects the negative electrode tab 32 and the negative electrode terminal 16. The negative electrode conductive member 60 is composed of a single metal plate (a copper plate in the present embodiment). The copper plate is preferably foil-shaped. The negative electrode conductive member 60 exists between the lid 13 of the case 11 and the electrode assembly 14.

  The negative electrode conductive member 60 includes a negative electrode first joint portion 61 that is disposed relatively closer to the lid 13. Further, as shown in FIG. 4, the negative electrode conductive member 60 includes a negative electrode second joint portion 62 disposed closer to the electrode assembly 14 than the negative electrode first joint portion 61, and the negative electrode first joint portion 61 and the negative electrode A curved negative third bonding portion 63 connecting the second bonding portion 62. In the negative electrode first joint portion 61, each negative electrode tab 32 is welded to a surface (lower surface) facing the tab side end surface 14 c of the electrode assembly 14, and the negative electrode first joint portion 61 and each negative electrode tab 32 are electrically connected. It is connected. The negative electrode first joint 61 of the negative electrode conductive member 60 serves as a connection portion with the negative electrode tab 32.

  The negative electrode terminal 16 includes a prismatic negative electrode head portion 71 and a negative electrode shaft portion 72 that protrudes from the seating surface of the negative electrode head portion 71 and has a thread groove on the outer peripheral surface. The negative electrode shaft portion 72 protrudes out of the case 11 through a through hole 13 b provided in the lid 13. The negative electrode shaft portion 72 is inserted through an insulating O-ring 73. The negative electrode shaft portion 72 is inserted through an insulating flanged ring 74. The flanged ring 74 has a cylindrical shape that fits into the through hole 13b.

  A nut 75 is screwed onto the negative electrode shaft portion 72 from above the flanged ring 74, and the negative electrode terminal 16 and the lid 13 are unitized. The flanged ring 74 is interposed between the negative electrode shaft portion 72 and the peripheral edge portion of the through hole 13 b of the lid 13 and between the nut 75 and the lid 13.

  The secondary battery 10 includes a current interrupting member 80 provided on a current path between the negative electrode terminal 16 that is an electrode terminal of one polarity and the electrode assembly 14. Note that the conductive member connected to the electrode terminal of one polarity (negative electrode 16) is a negative electrode conductive member 60. The current interrupting member 80 is an operating member that is operated by gas generated in the case.

  The secondary battery 10 also includes a caulking member 88 that unitizes the insulating negative electrode insulating member 87 that covers the seating surface and the outer peripheral surface of the negative electrode head 71, the negative electrode head 71, and the current interrupting member 80. ing. The negative electrode insulating member 87 regulates the contact between the lid 13 and the negative electrode head 71 and is attached to the negative electrode head 71 from the lid 13 side.

  The case 11 of the secondary battery 10 is provided with a pressure release valve 90 as shown in FIGS. The pressure release valve 90 of this embodiment is located on the lid 13 of the case 11. The pressure release valve 90 has a thin plate-like valve body 91 that is thinner than the plate thickness of the lid 13. The valve body 91 is located at the bottom of a recess provided in the upper surface of the lid 13 and is formed integrally with the lid 13. Further, the surface of the valve body 91 has an intersecting cleavage groove 92. The pressure release valve 90 receives pressure from the gas generated in the case 11. The pressure release valve 90 opens the pressure inside the case 11 outside the case by cleaving from the intersection of the cleavage grooves 92 when the pressure inside the case 11 exceeds the set pressure.

  In addition, as shown in FIGS. 1, 3, and 5, the secondary battery 10 includes an insulating cover 100 disposed between the positive electrode first joint 41 and the negative electrode first joint 61 and the lid 13. ing. The insulating cover 100 accommodates the electrode assembly 14 in the case main body 12 and is positioned on the joining portion S side in a state where the lid 13 is joined. In addition, the insulating cover 100 faces the tab-side end surface 14c, which is the surface of the electrode assembly 14, in the disposed state. The insulating cover 100 is made of, for example, resin. The insulating cover 100 includes a rectangular plate-shaped main body portion 101 and an upright portion 102 that rises downward from an end portion of the main body portion 101 in the short direction. Further, a communication hole 103 is formed in the body portion 101 of the insulating cover 100 at a portion facing the pressure release valve 90. As shown in FIG. 4, the pressure release valve 90 and the communication hole 103 are located between the positive electrode tab 31 and the negative electrode tab 32, so that the gas generated in the case 11 passes through the communication hole 103. It flows to 90.

  As shown in FIGS. 3 and 4, a plurality of holding tapes t1, t2, t3, t4, t5, and t6 are attached to the electrode assembly 14. Each holding tape t <b> 1 to t <b> 6 holds the electrode assembly 14 in the stacking direction of the positive electrode 21 and the negative electrode 22. The holding tapes t1 and t2 are attached to the first flat surface 14a, the tab-side end surface 14c, and the second flat surface 14b. The holding tapes t1 and t2 are affixed at predetermined intervals in the direction along the long sides of the first plane 14a and the second plane 14b. In addition, the direction along each long side of the 1st plane 14a and the 2nd plane 14b corresponds with the direction along the long side of the tab side end surface 14c. The holding tapes t3 and t4 are attached to the first flat surface 14a, the side surface 14e, and the second flat surface 14b. The holding tapes t5 and t6 are attached to the first flat surface 14a, the side surface 14f, and the second flat surface 14b. The holding tapes t3 to t6 are affixed at predetermined intervals in the direction along the short sides of the first plane 14a and the second plane 14b. The holding tapes t <b> 1 to t <b> 6 are pasted from one surface (first plane 14 a) extending along the direction orthogonal to the stacking direction of the electrode assembly 14 to the other surface (second plane 14 b).

  As shown in FIG. 5, in the state where the electrode assembly 14 is accommodated in the case 11 and the insulating cover 100 is disposed, the tab-side end surface 14 c of the electrode assembly 14 has a cover facing region d <b> 1 that faces the insulating cover 100. Can be projected. Further, as shown in FIG. 5, in the state where the electrode assembly 14 is accommodated in the case 11, the tab-side end surface 14c of the electrode assembly 14 has terminal facing regions d2, d3 facing the positive terminal 15 and the negative terminal 16. Can be projected. For this reason, in this embodiment, the tab side end surface 14 c of the electrode assembly 14 is a surface having a portion facing the insulating cover 100, the positive electrode terminal 15, and the negative electrode terminal 16.

  In this embodiment, the portion of the tab side end surface 14c that does not overlap the cover facing region d1 is set as the attachment position of the holding tapes t1 and t2. Further, in this embodiment, the holding tapes t1 and t2 have portions where they overlap with the terminal facing regions d2 and d3 described above as the pasting positions. As a result, the holding tape t <b> 1 is attached so as to be positioned immediately below the positive electrode terminal 15. Further, the holding tape t <b> 2 is attached so as to be located immediately below the negative electrode terminal 16.

  The holding tape t <b> 1 is attached so as to hang in the stacking direction of the electrode assembly 14. The holding tape t1 is positioned such that one end t1a along the stacking direction is along the end of the tab side end surface 14c, and the other end t1b along the stacking direction is from one end 101a of the insulating cover 100. Is also pasted to be located outside. The end of the tab side end surface 14c is a portion located at a corner where the tab side end surface 14c and the side surface 14f intersect. Further, the outside of the end portion 101 a of the insulating cover 100 is a portion located near the corner where the tab side end surface 14 c and the side surface 14 f intersect, that is, near the short side wall 12 c of the case body 12. Thereby, the holding tape t1 is located near the end of the tab side end surface 14c.

  The holding tape t <b> 2 is attached so as to be hung in the stacking direction of the electrode assembly 14. The holding tape t2 is positioned so that one end t2a along the laminating direction is along the end of the tab side end surface 14c, and the other end t2b along the laminating direction is from the other end 101b of the insulating cover 100. Is also pasted to be located outside. The end of the tab side end surface 14c is a part located at the corner where the tab side end surface 14c and the side surface 14e intersect. Further, the outside of the end portion 101 b of the insulating cover 100 is a portion located near the corner where the tab side end surface 14 c and the side surface 14 e intersect, that is, near the short side wall 12 b of the case body 12. Thereby, the holding tape t2 is located near the end of the tab side end surface 14c.

  The holding tapes t1 and t2 are tapes having the same or substantially the same width. As shown in FIGS. 4 and 5, the widths of the holding tapes t1 and t2 are the lengths in the direction along the long side direction of the first plane 14a and the second plane 14b. The lengths of the holding tapes t1 and t2 in the direction along the direction (direction orthogonal to the width) on the first plane 14a, the tab-side end surface 14c, and the second plane 14b are the same or substantially the same.

  A valve facing region d4 that faces the pressure release valve 90 can also be projected onto the tab side end surface 14c. In this embodiment, the holding tape is not affixed to the portion overlapping the valve facing region d4. That is, the portion of the tab side end surface 14c on which the valve facing region d4 is projected is in an exposed state. For this reason, for example, the gas generated at the time of abnormality flows to the pressure release valve 90 through the communication hole 103 without the flow path being blocked by the holding tape.

Next, the operation of the secondary battery 10 of this embodiment will be described.
When manufacturing the secondary battery 10, the positive electrode terminal 15 fixed to the lid 13 and the electrode assembly 14 joined to the negative electrode terminal 16 are inserted into the case body 12, and after the insertion, the case body 12 and the lid 13 are inserted. Are joined by welding. In the secondary battery 10 of this embodiment, the tab-side end surface 14 c of the electrode assembly 14 is located near the joint S between the case body 12 and the lid 13. For this reason, when a foreign material is generated when the case body 12 and the lid 13 are joined and the foreign material remains in the case 11, the foreign material may drop onto the tab side end surface 14c due to vibration or the like, for example. There is.

  However, in the secondary battery 10 of this embodiment, the insulating cover 100 is disposed to face the tab side end surface 14c, and the holding tape t1 is not overlapped with the cover facing region d1 projected on the tab side end surface 14c. , T2 are located. That is, as shown in FIG. 5, the tab-side end surface 14c has a small portion exposed when the tab-side end surface 14c is viewed in plan by the insulating cover 100 and the holding tapes t1 and t2. Thereby, even if the foreign matter remaining in the case 11 falls, the foreign matter falls toward the insulating cover 100 and the holding tapes t1 and t2 located on the joint S side.

Therefore, according to the present embodiment, the following effects can be obtained.
(1) Since the foreign matter in the case 11 falls on the insulating cover 100 and the holding tapes t1 and t2, it is suppressed that the foreign matter falls directly on the tab side end surface 14c of the electrode assembly 14. Therefore, it is possible to prevent foreign matter from entering the electrode assembly 14.

  (2) The holding tapes t <b> 1 and t <b> 2 are located immediately below the positive electrode terminal 15 and the negative electrode terminal 16. For this reason, it is possible to suppress the entry of foreign matter from the gap between the positive electrode terminal 15 or the negative electrode terminal 16 and the electrode assembly 14.

  (3) Since the holding tapes t1 and t2 are positioned at the end of the tab side end surface 14c of the electrode assembly 14, the electrode assembly 14 can be satisfactorily held while suppressing entry of foreign matter. Thereby, the short circuit of the electrode which comprises the electrode assembly 14 etc. can be avoided.

  (4) The holding tapes t <b> 1 and t <b> 2 are located at portions that do not overlap the insulating cover 100. The holding tapes t1 and t2 have a certain width. For this reason, by eliminating the overlap between the insulating cover 100 and the holding tapes t1 and t2, the exposed portion of the tab-side end surface 14c can be efficiently covered using the width of the holding tapes t1 and t2. .

In addition, you may change the said embodiment as follows.
The arrangement (including the number) of the holding tapes t1 and t2 on the tab side end surface 14c of the electrode assembly 14 may be changed. The holding tapes t1 and t2 only need to be positioned in a portion that does not overlap the cover facing region d1. In this case, it is preferable that the holding tape is not located also in the valve facing region d4.

  The holding tapes t1 and t2 do not have to overlap the terminal facing areas d2 and d3 as a whole. That is, it is only necessary that part of the holding tapes t1 and t2 overlap the terminal facing areas d2 and d3.

In addition, the holding tapes t1 and t2 may be attached with an interval to the end of the tab side end surface 14c.
○ The configuration of the insulating cover 100 may be changed. In the embodiment, the structure is integrated so as to cover both the positive electrode conductive member 40 and the negative electrode conductive member 60, but the insulating cover that covers the positive electrode conductive member 40 and the insulating cover that covers the negative electrode conductive member 60 are separated. The configuration may be acceptable.

In the electrode assembly 14, the arrangement (including the number) of the holding tapes t3 to t6 on the side surfaces 14e and 14f may be changed. A holding tape may be attached to the bottom surface 14d side.
In addition, the specific configuration of the current interrupting member 80 may be changed.

  (Circle) the electric current interruption member 80 may not be integrated with the electrode terminal. For example, the energization path may be configured between the negative electrode first bonding portion 61 and the negative electrode second bonding portion 62, and the energization path may be blocked by receiving gas pressure.

  The electrode terminal of one polarity provided with the current interrupting member 80 may be used as the positive electrode terminal 15. At this time, the conductive member connected to the positive electrode terminal 15 which is an electrode terminal of one polarity is the positive electrode conductive member 40.

○ The specific configuration of the pressure release valve 90 may be changed. For example, the shape of the valve body 91 and the shape of the cleavage groove 92 may be changed.
The specific configuration of the electrode assembly 14 may be changed. For example, the shapes of the positive electrode 21, the negative electrode 22, and the separator 23 may be changed. For example, a square in front view may be used.

The secondary battery 10 may include either the current interrupting member 80 or the pressure release valve 90 as an operating member.
The embodiment can also be applied to power storage devices other than secondary batteries, such as capacitors.

The embodiment may be embodied in the secondary battery 10 in which the current interrupting member 80 is not mounted.
The secondary battery 10 is not limited to being mounted on a vehicle, but may be a stationary battery used in a house or the like.

  The present invention may be applied not only to the stacked secondary battery 10 but also to a wound secondary battery configured to satisfy the same conditions as in the embodiment. A wound secondary battery has a structure in which a belt-like positive electrode and a belt-like negative electrode are wound and laminated in layers. The above condition is that the positive electrode conductive member 40 and the negative electrode conductive member 60 respectively connected to the positive electrode tab 31 and the negative electrode tab 32 are located on the joint S side of the case body 12 and the lid 13, and these positive electrode conductive members 40 and the insulating cover 100 covering the negative electrode conductive member 60 is located.

  DESCRIPTION OF SYMBOLS 10 ... Secondary battery as an electrical storage device, 11 ... Case, 12 ... Case main body, 13 ... Cover, 14 ... Electrode assembly, 14c ... Tab side end surface as a surface of an electrode assembly, 15 ... Positive electrode terminal as an electrode terminal 16 ... Negative electrode terminal as electrode terminal, 31 ... Positive electrode tab, 32 ... Negative electrode tab, 40 ... Positive electrode conductive member as conductive member, 60 ... Negative electrode conductive member as conductive member, 100 ... Insulating cover, d1 ... Cover facing region , D2, d3 ... terminal facing region, t1 to t6 ... holding tape, S ... junction, t1a, t1b, t2a, t2b ... end, 101a, 101b ... end.

Claims (5)

An electrode assembly in which electrodes of different polarities are alternately stacked in a state of being insulated from each other;
A case in which the electrode assembly is accommodated;
A conductive member electrically connected to a tab protruding from the end of the electrode;
An electrode terminal electrically connected to the conductive member;
An insulating cover for insulating the connecting portion between the tab and the conductive member and the case;
A holding tape pasted from one surface to the other surface extending along a direction orthogonal to the stacking direction of the electrode assembly,
The case has a case body and a lid joined to the case body,
The insulating cover is located on the joint side of the case body and the lid;
A power storage device in which a cover facing region facing the insulating cover is projected on a surface of the electrode assembly facing the insulating cover, and the holding tape is located in a portion not overlapping the cover facing region.   2. The power storage device according to claim 1, wherein a terminal facing region facing the electrode terminal is projected on the surface of the electrode assembly, and at least a part of the holding tape is located in a portion overlapping the terminal facing region. apparatus.   The power storage device according to claim 1, wherein the holding tape is located at an end of the surface of the electrode assembly. The holding tape is attached to the electrode in the stacking direction,
The power storage device according to any one of claims 1 to 3, wherein an end portion of the holding tape along the stacking direction is located outside an end portion of the insulating cover.   The power storage device according to any one of claims 1 to 4, wherein the power storage device is a secondary battery.