JP2017183619A - Power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve improvement of a structure of a power storage device and a simplification of a manufacturing method while improving characteristics of the power storage device.SOLUTION: A power storage device includes: a bottomed cylinder-like container 10 constructing a negative electrode terminal; a wound electrode plate group 21 housed in the container 10; a container lid 30 constructing a positive electrode terminal; a positive electrode collector member 28; and a negative electrode collector member 29, and the container lid 30 is constructed as follows. The container lid 30 is a disc-like member made of a conductive material, and includes: a convex part projected to an upper surface side of a central part; an outer peripheral part of the convex part; and a positive electrode lead plate 30c extended to a lower part of the convex part. The positive electrode lead plate 30c is electrically connected to the positive electrode collector member 28, and further the wound electrode plate group 21 or the like is sealed by the container lid 30 and the container 10. According to the above construction, a component part number of the container lid can be reduced, a manufacturing step of the container lid can be simplified, and the resistance of the container lid can be reduced.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electricity storage device, for example, a non-aqueous electrolyte electricity storage device such as a lithium ion capacitor.

  Nonaqueous electrolyte storage devices such as lithium ion capacitors have the advantages of high energy density, low self-discharge and good cycle performance. Therefore, in recent years, it is expected that the nonaqueous electrolyte storage device is used as a power source for automobiles such as hybrid cars and electric cars by increasing the size or capacity.

  For example, in Patent Document 1 (International Publication No. 2012/039497), a wound electrode plate group in which a positive and negative electrode plate is wound around a shaft core through a separator in a bottomed cylindrical container is electrolyzed. A wound type electricity storage device housed with a liquid is disclosed.

International Publication No. 2012/039497

  The present inventor is engaged in research and development of non-aqueous electrolyte storage devices such as lithium ion capacitors, and is diligently studying its configuration and manufacturing process. For example, in the electricity storage device described in Patent Document 1, the number of parts of the upper lid portion (upper lid case, upper lid cap) is large, and the manufacturing process is complicated.

  Therefore, it is desired to solve such problems and improve the configuration of the electricity storage device and simplify the manufacturing process.

  An object of the present invention is to improve the configuration of a power storage device and simplify the manufacturing process while maintaining the characteristics of the power storage device.

  Of the embodiments disclosed in the present application, the outline of typical ones will be briefly described as follows.

  An electricity storage device shown in an embodiment disclosed in the present application includes a bottomed cylindrical container constituting a negative electrode terminal, a wound electrode plate group accommodated in the container, a positive electrode current collecting member, and a negative electrode current collector. An electric member, an electrolytic solution, and a lid member constituting a positive electrode terminal, and the wound electrode plate group includes a coating layer formed by applying a positive electrode active material mixture to a first metal foil, and A positive electrode plate having an uncoated portion of the first metal foil remaining along the coating layer, a coating layer formed by applying a negative electrode active material mixture to the second metal foil, and the coating layer A separator plate so that the uncoated portion of the positive electrode plate and the uncoated portion of the negative electrode plate protrude in opposite directions, respectively. A positive electrode current collecting member is formed at one end of the wound electrode plate group. The negative electrode current collector is welded to the uncoated portion of the negative electrode plate at the other end of the wound electrode plate group, and the lid member is electrically conductive. A disc-shaped member made of a functional material, connected to the convex portion protruding to the first surface side of the central portion, the outer peripheral portion of the convex portion, and the second surface side of the outer peripheral portion; A positive electrode terminal portion extending downward, and the positive electrode terminal portion is electrically connected to the positive electrode current collecting member, and the wound electrode plate group and the positive electrode are formed by the lid member and the container. The current collecting member, the negative electrode current collecting member, and the electrolytic solution are sealed.

  For example, in the electricity storage device, the convex portion and the outer peripheral portion are integrally formed of the conductive material, and the conductive material is a material containing aluminum.

  For example, in the electricity storage device, the lid member has a cleavage groove or a cleavage valve formed in the outer peripheral portion.

  For example, in the electricity storage device, the convex portion is an annular convex portion, and the lid member has a concave portion provided inside the annular convex portion.

  For example, the power storage device includes a nut in the recess.

  For example, in the electricity storage device, the nut is connected to a bus bar.

  For example, in the electricity storage device, the lid member has a projection formed on the first surface side of the convex portion.

  For example, in the electricity storage device, the projection is welded to a bus bar.

  According to the electricity storage device disclosed in the following representative embodiment disclosed in the present application, the number of components of the lid member can be reduced. Moreover, the manufacturing process of the lid member can be simplified. In the lithium ion capacitor, the resistance of the lid member can be reduced.

1 is a cross-sectional view showing a configuration of a lithium ion capacitor according to Embodiment 1. FIG. 3 is a diagram illustrating a configuration of a wound electrode plate group of the lithium ion capacitor according to Embodiment 1. FIG. 5 is a cross-sectional view showing a manufacturing process (assembly process) of the lithium ion capacitor of Embodiment 1. FIG. 1 is a cross-sectional view showing a configuration of a lithium ion capacitor according to Embodiment 1. FIG. 3 is a diagram showing a configuration of a container lid of the lithium ion capacitor according to Embodiment 1. FIG. It is sectional drawing which shows the structure of the lithium ion capacitor of a comparative example. It is a figure which shows the structure of the container lid of the lithium ion capacitor of a comparative example. It is sectional drawing which shows an example of the shape of a cleavage part. 6 is a diagram showing a configuration of a container lid of a lithium ion capacitor of application example 1 of Embodiment 2. FIG. 6 is a diagram showing a configuration of a container lid of a lithium ion capacitor of application example 2 of Embodiment 2. FIG. 6 is a diagram showing a configuration of a container lid of a lithium ion capacitor of application example 3 of Embodiment 2. FIG. 12 is a plan view showing another configuration of the container lid of the lithium ion capacitor of Application Example 3 of Embodiment 2. FIG.

  In the following embodiments, members having the same function are denoted by the same or related reference numerals, and repeated description thereof is omitted. In the drawings used in the embodiments, hatching may be omitted even in a cross-sectional view in order to make the drawings easy to see. Even a plan view may be hatched. In the cross-sectional view and the plan view, the size of each part does not correspond to the actual device, and a specific part may be displayed relatively large for easy understanding of the drawing.

(Embodiment 1)
Hereinafter, the power storage device of the present embodiment will be described in detail with reference to the drawings.

[Description of structure]
FIG. 1 is a cross-sectional view showing the configuration of the lithium ion capacitor of the present embodiment. FIG. 2 is a diagram showing a configuration of the wound electrode plate group of the lithium ion capacitor of the present embodiment.

  As shown in FIG. 1, the lithium ion capacitor (power storage device) includes a container (can) 10, an electrode plate group unit 20, and a container lid (lid member) 30. The container 10 constitutes a negative electrode terminal, and the container lid 30 constitutes a positive electrode terminal.

  The container 10 is a bottomed cylindrical container made of steel plated with nickel, for example. Moreover, the bottom part of the container 10 is provided with the bulging part and the cyclic | annular bottom wall part around it. The strength of the container 10 can be increased by the bulging portion and the annular bottom wall portion.

  The electrode plate group unit 20 includes a wound electrode plate group 21, a positive electrode current collecting member 28, and a negative electrode current collecting member 29. The electrode plate group unit 20 is housed in the container 10.

  As shown in FIG. 2A, the wound electrode plate group 21 includes a shaft core 22, a positive electrode plate 23, a first separator 24, a negative electrode plate 25, and a second separator 26. A laminated body in which these are sequentially laminated is wound around the shaft core 22. Note that a metallic lithium supply body 27 is disposed in the wound electrode plate group 21 before doping.

  As shown in FIG. 2B, the metal lithium supply body 27 includes copper foils 27a and 27c, which are metal lithium support members, and a thin plate-like metal lithium 27b sandwiched therebetween. A large number of through holes are formed in the copper foils 27a and 27c (not shown).

  The positive electrode plate 23 includes, for example, an aluminum foil (metal foil, positive electrode current collector) 23a and a positive electrode active material mixture (coating layer) 23b applied on both surfaces thereof. As the positive electrode active material mixture 23b, for example, a mixture of activated carbon, a binder, and a dispersant can be used. The aluminum foil 23a includes a coated portion where a large number of through holes are formed and a positive electrode active material mixture is applied, and an uncoated portion where the through holes are not formed, formed along the longitudinal direction of the coated portion. (Exposed portion of aluminum foil).

  The negative electrode plate 25 includes, for example, a copper foil (metal foil, negative electrode current collector) 25a and a negative electrode active material mixture (coating layer) 25b applied on both surfaces thereof. As the negative electrode active material mixture 25b, for example, a mixture of amorphous carbon capable of inserting and extracting lithium ions, a binder, and a conductive additive can be used. The copper foil 25a includes a coated portion in which a large number of through holes are formed, and an uncoated portion (exposed portion of the aluminum foil) that is formed along the longitudinal direction of the coated portion and has no through holes. Have.

  As the first and second separators 24 and 26, for example, a porous substrate such as kraft paper can be used. For example, a hollow cylindrical member made of polypropylene can be used as the shaft core 22.

  The positive electrode plate 23, the first separator 24, the negative electrode plate 25, and the second separator 26 are wound around the shaft core 22, thereby forming a wound electrode plate group 21. At this time, the uncoated portion of the positive electrode plate 23 and the uncoated portion of the negative electrode plate 25 are wound so as to protrude in opposite directions. In the wound electrode plate group 21, the above-described metallic lithium supply body 27 is also wound. For example, the metal lithium supply body 27 is disposed between the positive electrode plates 23 divided into two. Moreover, the winding terminal part of this winding electrode group 21 is being fixed with the adhesive tape.

  The metallic lithium supply body 27 is arranged in advance in the wound electrode plate group 21, connected to the negative electrode, and left for a predetermined period, whereby the metallic lithium is dissolved and inserted in the negative electrode active material of the negative electrode plate 25 ( doping).

  FIG. 2C is an exploded perspective view of the electrode plate group unit 20. From the top of the figure, a positive electrode current collector 28, a wound electrode plate group 21, and a negative electrode current collector 29 are shown.

  As shown in the lower diagram of FIG. 2C, the negative electrode current collecting member 29 is, for example, a disk-shaped member, and has a recess 29a in the center. The negative electrode current collecting member 29 is made of, for example, a metal material obtained by performing nickel plating on nickel or copper. The negative electrode current collecting member 29 is welded to an uncoated portion of the copper foil of the negative electrode plate 25 of the wound electrode plate group 21. For example, the negative electrode current collecting member 29 is placed on the uncoated portion of the copper foil of the negative electrode plate 25 of the wound electrode plate group 21 and welded by laser welding. In FIG. 1, the welded portion is indicated by “29d”. The lower surface (back surface) of the recess 29a of the negative electrode current collecting member 29 is in contact with the bottom (bulge) of the container 10, and the outer peripheral portion 29b of the recess 29a is in contact with the annular bottom wall portion of the bottom of the container 10 (see FIG. 1). ).

  As shown in the upper diagram of FIG. 2C, the positive electrode current collecting member 28 is, for example, a ring-shaped member having a circular hole 28a in the central portion. The positive electrode current collector 28 is made of, for example, aluminum (including an aluminum alloy). Further, the positive electrode current collector 28 has a positive electrode lead plate (positive electrode terminal part) 28c. The positive electrode lead plate 28c is joined to the upper surface (surface) of the positive electrode current collector 28, that is, the upper surface of the outer peripheral portion 28b of the hole 28a. The positive electrode lead plate 28c is made of, for example, a member in which ribbon-like aluminum foils are laminated. The positive electrode current collector 28 is welded to an uncoated portion of the positive electrode plate 23 of the wound electrode plate group 21. For example, the positive electrode current collecting member 28 is placed on the uncoated portion of the positive electrode plate 23 of the wound electrode plate group 21 and welded by laser welding. In FIG. 1, the welded portion is indicated by “28d”.

[Manufacturing process]
3 and 4 are cross-sectional views showing the manufacturing process (assembly process) or configuration of the lithium ion capacitor of the present embodiment.

  First, as shown in FIG. 3, the electrode plate group unit 20 is accommodated in the container 10. As described above, the lower surface of the recess (29a) of the negative electrode current collecting member 29 is in contact with the bottom (bulged portion) of the container 10, and the outer peripheral portion (29b) of the recess (29a) is the annular bottom of the bottom of the container 10. Touch the wall. Next, the recess 29a of the negative electrode current collecting member 29 and the bottom portion (bulging portion) of the container 10 are welded by spot welding. Thereby, the negative electrode current collecting member 29 and the container 10 can be electrically connected, and the electrode plate group unit 20 can be fixed inside the container 10. Further, the positive electrode current collecting member 28 is fixed to the upper side wall of the container 10 via an insulating ring member 41.

  Next, as shown in FIG. 4, the container lid 30 constituting the positive electrode terminal is disposed above the electrode plate group unit 20. FIG. 5 is a diagram showing the configuration of the container lid of the lithium ion capacitor of the present embodiment. 5A is a cross-sectional view, FIG. 5B is a plan view seen from above, and FIG. 5C is a plan view seen from below.

  As shown in FIGS. 4 and 5, the container lid 30 includes a lid cap 30a and a positive electrode lead plate 30c. The lid cap 30a is a disk-shaped member, and has a convex portion 30ac at the center and an outer peripheral portion (flat portion) 30ae of the convex portion 30ac. The height of the protrusion 30ac (H in FIG. 5A) is, for example, about 5 mm. The lid cap 30a is made of aluminum (a conductive material including an aluminum alloy). The thickness of aluminum is about 1.5 mm, for example. The positive electrode lead plate 30c is joined to the lower surface of the outer peripheral portion 30ae of the lid cap 30a. The hatched portion in FIG. 5C is a joined portion (welded portion). The positive electrode lead plate 30c is made of, for example, a member in which ribbon-like aluminum foils are stacked. Further, a cleaving portion is provided on the lower surface of the outer peripheral portion 30ae of the lid cap 30a. Here, a cleavage groove 30g is formed as the cleavage portion. The cleavage groove 30g is cleaved when the pressure in the container of the lithium ion capacitor exceeds a predetermined pressure.

  The positive electrode lead plate 30 c of the container lid 30 is joined to the positive electrode lead plate 28 c of the positive electrode current collecting member 28.

Next, a non-aqueous electrolyte (not shown) is injected into the container 10. Examples of the non-aqueous electrolyte include phosphorus hexafluoride as a lithium salt in a solvent in which ethylene carbonate (EC), dimethyl carbonate (DMC), and diethyl carbonate (DEC) are mixed at a volume ratio of 30:50:20. A solution in which lithium acid (LiPF ₆ ) is dissolved can be used. The non-aqueous electrolyte is injected into the container 10 in an amount that can infiltrate the entire electrode plate group unit 20.

  Next, the container lid 30 is mounted on the upper part of the container 10 so that the positive electrode lead plates (28c, 30c) are folded. At this time, the container lid 30 is disposed on the annular convex portion at the top of the container 10 via the insulating member 43. By this insulating member 43, the container lid 30 and the container 10 are electrically insulated.

  Next, the annular wall portion at the top of the container lid 30 is curled (caulked) inward. Accordingly, the container lid 30 is fixed between the annular wall portion and the annular convex portion with the insulating member 43 interposed therebetween (see FIG. 1). As a result, the electrode plate group unit 20 and the non-aqueous electrolyte (not shown) are sealed by the container 10 and the container lid 30. The lithium ion capacitor can be assembled through the above steps.

  As described above, in the present embodiment, the number of members constituting the container lid 30 is reduced as compared with the case of the comparative example described later, so that the part cost can be reduced. Moreover, the manufacturing process of the container lid 30 can be simplified. In addition, the characteristics of the lithium ion capacitor can be improved.

  FIG. 6 is a cross-sectional view showing a configuration of a lithium ion capacitor of a comparative example. FIG. 7 is a diagram illustrating a configuration of a container lid of a lithium ion capacitor of a comparative example. FIG. 7A is a side view, FIG. 7B is a plan view seen from above, and FIG. 7C is a plan view seen from below.

  As shown in FIGS. 6 and 7, the container lid 30 of the comparative example includes a lid case 30b disposed on the lower side, a lid cap 30a disposed on the upper side, and a positive electrode lead plate 30c. The lid case 30b is formed with a cleavage groove 30g that is cleaved by an increase in internal pressure. The lid cap 30a has a hole 30h. The container lid 30 has a positive electrode lead plate 30c. The positive electrode lead plate 30c is joined to the lower surface of the lid case 30b. The positive electrode lead plate 30c is made of, for example, a member in which ribbon-like aluminum foils are stacked. The positive electrode lead plate 30 c of the container lid 30 is joined to the positive electrode lead plate 28 c of the positive electrode current collector 28. The hatched portion in FIG. 7C is a joined portion (welded portion). The container lid 30 includes a lid case 30b, a lid cap 30a, and a positive electrode lead plate 30c. The lid case 30b to which the positive electrode lead plate 30c is bonded, and the lid cap 30a are stacked, and the lid case 30b is laminated. It is assembled by curling (caulking) the periphery of each. More specifically, (1) the lid case 30b and the positive electrode lead plate 30c are ultrasonically bonded. Next, (2) the lid case 30b and the lid cap 30a are overlapped and curled (caulked) so as to cover the end of the lid cap 30a on the outer periphery of the lid case 30b. Next, (3) the overlapping portion of the lid case 30b and the lid cap 30a is joined by resistance welding (see the hatched portion in FIG. 7C). Thereafter, (4) the container lid 30 is washed.

  On the other hand, in this embodiment, since the container lid 30 is configured by the lid cap 30a and the positive electrode lead plate 30c, the number of component parts of the container lid 30 can be reduced as compared with the comparative example. Thereby, reduction of component cost can be aimed at. In the present embodiment, the container lid 30 is manufactured in a short process of (1) ultrasonic bonding the lid case 30b and the positive electrode lead plate 30c, and then (2) cleaning the container lid 30. can do. Thus, the manufacturing process of the container lid can be simplified. The lid case 30b can be formed by punching out an aluminum plate into a circle by pressing. Thus, the lid case 30b can be processed as a single piece of aluminum. The lid case 30b of the present embodiment does not require the hole 30h as in the comparative example.

  Further, in the assembled lithium ion capacitor, the resistance of the container lid 30 can be reduced. That is, the container lid 30 of the comparative example is composed of three components (the lid cap 30a, the lid case 30b, and the positive electrode lead plate 30c), and the resistance increases because the number of component parts is large. Further, the lid cap 30a is made of steel, and the lid case 30b and the positive electrode lead plate 30c are made of aluminum, so that the connection resistance between different materials increases. On the other hand, in the present embodiment, since the number of component parts of the container lid 30 is small, the resistance can be reduced. Further, the resistance can be further reduced by using the same material (made of aluminum) for the lid case 30b and the positive electrode lead plate 30c.

(Embodiment 2)
In this embodiment, an application example of the first embodiment will be described. Note that the description of the same configuration as that of Embodiment 1 is omitted. Hereinafter, application examples of the present embodiment will be described in detail with reference to the drawings.

(Application 1)
In the first embodiment, the sectional shape of the cleavage groove 30g on the lower surface of the outer peripheral portion 30ae of the lid cap 30a is triangular, but the sectional shape of the cleavage groove 30g is not limited to this shape. FIG. 8 is a cross-sectional view showing an example of the shape of the cleavage portion. FIG. 8A shows the case of the triangular shape described in the first embodiment, and FIG. 8B shows the case of another shape. As shown in FIG. 8 (b), the cross-sectional shape is a rectangular cleavage groove, and a triangular cut may be provided on the bottom surface (upper part in the drawing).

  The thickness (t1) of the lid cap 30a is, for example, about 1.5 mm, and the thickness (t2) at the cleavage groove 30g, that is, the thickness of the thinnest portion of the lid cap 30a is, for example, 0. It is about 1 to 0.2 mm. Thus, by providing the cleaving groove 30g in the lid cap 30a, it is possible to release the pressure inside the cell when the lithium ion capacitor is abnormal and prevent rupture. Moreover, the width (W) of the cleavage groove 30g can be set to, for example, about 1.5 mm. For example, as shown in FIG. 5, the outer peripheral portion 30ae is provided with three cleavage grooves 30g having a central angle of 60 ° and an arcuate width of about 1.5 mm with a predetermined interval (central angle 30 °). Thus, for example, 2 to 6 arc-shaped cleavage grooves 30g having a central angle of about 45 ° to 90 ° may be provided. Moreover, you may provide the continuous cleavage groove | channel 30g whose center angle of a circular arc is about 180 degrees-270 degrees. In this way, the cleavage groove 30g can be provided in a wide range by using a region other than the welding region of the positive electrode lead plate 30c.

  Moreover, as shown in FIG.8 (c), you may provide the cleavage valve which provided the hole (through-hole) 30ah in the lid cap 30a, and block | closed this hole 30ah with resin 30i. Even with such a cleavage valve, the resin 30i is detached when the pressure in the container of the lithium ion capacitor exceeds a predetermined pressure, and the pressure inside the cell at the time of abnormality can be released to prevent the explosion.

  In Embodiment 1, the cleaving groove 30g is provided in the outer peripheral portion 30ae of the lid cap 30a. However, as shown in FIG. 9, the cleaving groove 30g is provided on the side surface of the convex portion 30ac of the lid cap (30a). Also good. Of course, a cleavage valve (30ah, 30i) may be provided on the side surface of the convex portion 30ac of the lid cap. FIG. 9 is a diagram showing the configuration of the container lid of the lithium ion capacitor of Application Example 1 of the present embodiment.

  As described above, when the cleavage groove 30g is provided in the outer peripheral portion 30ae of the lid cap 30a, it is preferable to provide the cleavage groove 30g in a region avoiding the welding region of the positive electrode lead plate 30c.

(Application example 2)
You may provide the nut insertion recessed part (dent) in the center part of the convex part 30ac of the cover cap 30a of Embodiment 1. FIG.

  FIG. 10 is a diagram showing the configuration of the container lid of the lithium ion capacitor of Application Example 2 of the present embodiment. 10A is a cross-sectional view, FIG. 10B is a plan view seen from the upper side, and FIG. 10C is a plan view seen from the lower side.

  As shown in FIG. 10, a nut insertion recess 30d is provided at the center of the projection 30ac of the lid cap 30a. In this case, the convex part 30ac of the lid cap 30a becomes an annular convex part, and the concave part 30ad is provided inside the annular convex part. For example, a hexagon nut 50 is inserted into the recess 30ad and fixed by welding or the like.

  Thus, the lithium ion capacitor can be connected to the bus bar (connecting metal fitting) using the hexagon nut 50. And a some lithium ion capacitor can be connected in parallel, for example via a bus-bar.

(Application 3)
In the application example 2, the lid cap 30a is provided with a recess for inserting a nut for connecting to the bus bar. However, the lid cap 30a may be provided with a projection for connecting to the bus bar. The projection is, for example, a protrusion provided on the material to be welded.

  FIG. 11 is a diagram showing the configuration of the container lid of the lithium ion capacitor of Application Example 3 of the present embodiment. 11A is a cross-sectional view, FIG. 11B is a plan view seen from above, and FIG. 11C is a plan view seen from below. FIG. 12 is a plan view showing another configuration of the container lid of the lithium ion capacitor of Application Example 3 of the present embodiment.

  As shown in FIG. 11, a protrusion 30ap is provided on the convex portion 30ac of the lid cap (30a). In this case, the protrusion 30ap of the lid cap is made of the same member as the lid cap, for example. A lithium ion capacitor can be connected to the bus bar by joining the protrusion 30ap and the bus bar (connecting metal fitting) by projection welding. And a some lithium ion capacitor can be connected in parallel, for example via a bus-bar.

  In FIG. 11, two protrusions 30ap are arranged side by side in the direction along the positive electrode lead plate 30c as shown in FIG. 11B, but as shown in FIG. 12, the two protrusions 30ap are arranged in the positive electrode lead plate. They may be arranged side by side in a direction orthogonal to (30c).

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say. For example, in the above embodiment, the container lid side is the positive electrode, but the container lid side may be the negative electrode. In this case, the container lid is preferably made of copper. Moreover, in the said embodiment, although the structure of the container cover was demonstrated taking the lithium ion capacitor as an example, it is applicable also as a container cover of a lithium ion battery other than this. Thus, it can be applied to various power storage devices.

  The present invention relates to an electricity storage device, and can be widely applied to, for example, non-aqueous electrolyte electricity storage devices such as lithium ion capacitors.

DESCRIPTION OF SYMBOLS 10 Container 20 Electrode plate group unit 21 Winding electrode plate group 22 Axle core 23 Positive electrode plate 23a Aluminum foil 23b Positive electrode active material mixture 24 Separator 25 Negative electrode plate 25a Copper foil 25b Negative electrode active material mixture 26 Separator 27 Metal lithium supply body 27a Copper foil 27b Metal lithium 27c Copper foil 28 Positive electrode current collecting member 28a Hole 28b Outer peripheral portion 28c Positive electrode lead plate 29 Negative electrode current collecting member 29a Depression 29b Outer peripheral portion 30 Container lid 30a Lid cap 30ac Convex portion 30ad Concave portion 30ae Outer peripheral portion 30ap Protruding portion 30b Lid case 30c Positive electrode lead plate 30g Cleavage groove 30ah Hole 30h Hole 30i Resin 41 Insulating ring member 43 Insulating member 50 Hexagon nut t1 Thickness t2 Thickness

Claims (8)

A bottomed cylindrical container constituting the negative electrode terminal, a wound electrode plate group accommodated in the container, a positive electrode current collecting member, a negative electrode current collecting member, an electrolyte, and a lid member constituting the positive electrode terminal; Have
The wound electrode plate group includes a coating layer formed by coating a positive electrode active material mixture on a first metal foil, and a positive electrode having an uncoated portion of the first metal foil remaining along the coating layer A negative electrode plate having a plate, a coating layer formed by coating a negative electrode active material mixture on a second metal foil, and an uncoated portion of the second metal foil remaining along the coating layer, The uncoated part of the positive electrode plate and the uncoated part of the negative electrode plate are each composed of a wound body of a laminated body laminated via a separator so as to protrude in the opposite direction,
The positive electrode current collector member is welded to the uncoated portion of the positive electrode plate at one end of the wound electrode plate group,
The negative electrode current collector member is welded to the uncoated portion of the negative electrode plate at the other end of the wound electrode plate group,
The lid member is a disk-shaped member made of a conductive material, and is connected to a convex portion protruding to the first surface side of the central portion, an outer peripheral portion of the convex portion, and a second surface side of the outer peripheral portion. And a positive electrode terminal portion extending to below the convex portion,
The positive terminal portion is electrically connected to the positive current collecting member,
The electricity storage device, wherein the wound electrode plate group, the positive electrode current collector, the negative electrode current collector, and the electrolyte are sealed by the lid member and the container. The electricity storage device according to claim 1, wherein
The convex portion and the outer peripheral portion are integrally formed of the conductive material,
The electrical storage device, wherein the conductive material is a material containing aluminum. The electricity storage device according to claim 1, wherein
The lid member is a power storage device having a cleavage groove or a cleavage valve formed in the outer peripheral portion. The electricity storage device according to claim 1, wherein
The convex portion is an annular convex portion,
The said cover member is an electrical storage device which has a recessed part provided inside the said cyclic | annular convex part. The electricity storage device according to claim 4,
An electricity storage device having a nut in the recess. The electricity storage device according to claim 5, wherein
An electricity storage device in which the nut is connected to a bus bar. The electricity storage device according to claim 1, wherein
The said cover member is an electrical storage device which has the projection formed in the said 1st surface side of the said convex part. The electricity storage device according to claim 7,
An electricity storage device, wherein the projection is welded to a bus bar.

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