WO2019186849A1

WO2019186849A1 - Battery, battery pack, power storage device, vehicle, and flying object

Info

Publication number: WO2019186849A1
Application number: PCT/JP2018/013045
Authority: WO
Inventors: 直樹岩村; 竹下　功一; 橋本　達也
Original assignee: 株式会社東芝
Priority date: 2018-03-28
Filing date: 2018-03-28
Publication date: 2019-10-03
Also published as: JP7011043B2; CN111886715A; CN111886715B; JPWO2019186849A1

Abstract

The present invention addresses the problem of providing a thin battery having a lead shape and excellent large current characteristics, a battery pack, a power storage device, a vehicle, and a flying object. A battery according to an embodiment comprises: an electrode group; an exterior member; a positive electrode terminal unit; and a negative electrode terminal unit. The flat plate-shaped electrode group includes: a positive electrode; a positive electrode current collector tab electrically connected to the positive electrode; a negative electrode; and a negative electrode current collector tab electrically connected to the negative electrode, wherein the positive electrode current collector tab wound in a flat plate shape is located on a first end surface, and the negative electrode current collector tab wound in a flat plate shape is located on a second end surface. The exterior member includes: an electrode group-side positive electrode lead electrically connected to the positive electrode current collector tab; an electrode group-side negative electrode lead electrically connected to the negative electrode current collector tab; a first exterior unit having a flange part in an opening part thereof; and a second exterior unit. The electrode group is accommodated in a space formed by welding the second exterior unit and the flange part of the first exterior unit.

Description

Batteries, battery packs, power storage devices, vehicles, and flying objects

Embodiments of the present invention relate to a battery, a battery pack, a power storage device, a vehicle, and a flying object.

Batteries such as a primary battery and a secondary battery generally include an electrode group including a positive electrode and a negative electrode, and an exterior member that houses the electrode group.

Currently, metal cans and laminate film containers are in practical use as exterior members. A metal can is obtained by deep drawing from a metal plate such as aluminum. In order to produce a can by deep drawing, the metal plate needs to have a certain thickness, which prevents a reduction in the thickness of the exterior member and leads to a loss in volume capacity. For example, when an outer can having a thickness of 0.5 mm is applied to a battery having a thickness of 13 mm, the ratio of the total thickness of the outer can to the battery thickness is approximately 7.7%. Since it is a thin battery, the leads in the battery are required to be accommodated in a compact manner by bending it in a complicated manner.

In the exterior member, the battery element and the electrode terminal are joined by a lead. Bending after joining is difficult to accommodate because the work space and the accommodation space are narrow. Also, if the thickness is such that it can be bent after joining, the leads will be thin and not suitable for large currents. Further, if the welded portion is bent after the lead is welded, the joined portion is easily peeled off, and a battery that is not bent after joining is desired from the viewpoint of quality.

International Publication No. 2016/204147

The problem to be solved by the present invention is to provide a battery, a battery pack, a power storage device, a vehicle, and a flying object having a lead shape with excellent large current characteristics in a thin battery.

The battery according to the embodiment includes a positive electrode, a positive electrode current collecting tab electrically connected to the positive electrode, a negative electrode, and a negative electrode current collecting tab electrically connected to the negative electrode, and the positive electrode current collector wound in a flat shape A flat electrode group in which a tab is positioned on the first end surface and a negative electrode current collecting tab wound in a flat shape is positioned on the second end surface, and an electrode group side positive electrode electrically connected to the positive electrode current collecting tab A first exterior part including a lead, a negative electrode lead on the electrode group side electrically connected to the negative electrode current collecting tab, a first exterior part having a flange part in the opening, and a flange of the first exterior part An exterior member in which an electrode group is housed in a space formed by welding the first and second exterior parts, and the first exterior part has a through-hole on the positive electrode current collecting tab side, and the head and the head A positive electrode external terminal including a shaft portion extending from the positive electrode terminal lead and a positive electrode terminal lead having a through hole, the head portion of the first exterior portion The positive electrode terminal portion protruding to the side, the shaft portion being inserted into the through hole of the positive electrode terminal lead, and the shaft portion being caulked and fixed to the first exterior portion and the positive electrode terminal lead, and the first exterior portion is on the negative electrode current collecting tab side A negative electrode external terminal including a head portion and a shaft portion extending from the head portion, and a negative electrode terminal lead having a through hole, the head portion projecting outside the first exterior portion, and the shaft portion Is inserted into the through hole of the negative electrode terminal lead, and the shaft portion includes a first exterior portion and a negative electrode terminal portion fixed by caulking to the negative electrode terminal lead. The positive electrode terminal lead has a first extension portion extending to the second exterior portion side. The first extended portion of the electrode group side positive lead is provided on the opposite side of the electrode group side positive lead from the electrode group side. The first extension of the positive terminal lead and the first extension of the electrode group side positive lead are welded. The first extension part of the welded positive electrode terminal lead and the tip end of the first extension part of the electrode group side positive electrode lead are in contact with the surface of the second exterior part parallel to the opening of the first exterior part. Vertical or nearly vertical. The negative electrode terminal lead has a first extension part extending to the second exterior part side. A first extending portion of the electrode group side negative electrode lead is provided on the side opposite to the electrode group side of the electrode group side negative electrode lead. The first extension of the negative terminal lead and the first extension of the electrode group side negative lead are welded. The first extension part of the welded negative electrode terminal lead and the tip of the first extension part of the electrode group side negative electrode lead are in contact with the surface of the second exterior part parallel to the opening of the first exterior part. Vertical or nearly vertical.

FIG. 1 is a schematic perspective view of the battery according to the first embodiment. 2A is an exploded perspective view of the battery shown in FIG. 1 as viewed from the positive electrode side. 2B is an exploded perspective view seen from the negative electrode side of the battery shown in FIG. FIG. 3 is a perspective view of the electrode group of the battery shown in FIG. FIG. 4 is a perspective view showing a state in which the electrode group is partially expanded. FIG. 5 is a cross-sectional view obtained when the positive electrode portion of FIG. 1 is cut along the battery long side direction. FIG. 6 is a cross-sectional view obtained when the negative electrode portion of FIG. 1 is cut along the battery long side direction. FIG. 7 is a perspective view of the battery shown in FIG. 1 with a terminal portion fixed to the first exterior portion. FIG. 8A is a plan view of the second exterior portion, and FIG. 8B is a plan view of the first exterior portion. FIGS. 9A, 9B, 9C, and 9D are three views showing the manufacturing process of the battery of the first embodiment. FIG. 10A is a process diagram showing an assembly process of a battery containing a plurality of electrode groups. FIG. 10B is a process diagram illustrating an assembling process of a battery containing a plurality of electrode groups. FIG. 10C is a process diagram illustrating an assembling process of a battery containing a plurality of electrode groups. FIG. 10D is a process diagram illustrating an assembly process of a battery that accommodates a plurality of electrode groups. FIG. 11A is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery long side direction. FIG. 11B is a cross-sectional view obtained when the negative electrode portion of FIG. 1 in the modification is cut along the battery long side direction. 12 is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery longitudinal direction. FIG. 13A is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery long side direction. FIG. 13B is a cross-sectional view obtained when the negative electrode portion of FIG. 1 in the modification is cut along the battery long side direction. FIG. 14 is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery longitudinal direction. FIG. 15A is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery long side direction. FIG. 15B is a cross-sectional view obtained when the negative electrode portion of FIG. 1 in the modification is cut along the battery long side direction. 16 is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery longitudinal direction. FIG. 17 is a cross-sectional view obtained when the positive electrode portion of FIG. 1 in the modification is cut along the battery longitudinal direction. FIG. 18 is a schematic diagram illustrating a first example of the battery pack according to the second embodiment. FIG. 19 is a schematic diagram illustrating a second example of the battery pack according to the second embodiment. FIG. 20 is a schematic diagram of the power storage device of the third embodiment. FIG. 21 is a schematic view of a vehicle according to the fourth embodiment. FIG. 22 is a schematic view of the flying object of the fifth embodiment.

Hereinafter, embodiments will be described with reference to the drawings. In addition, the same code | symbol shall be attached | subjected to a common structure through embodiment, and the overlapping description is abbreviate | omitted. Each figure is a schematic diagram for promoting explanation and understanding of the embodiment, and its shape, dimensions, ratio, etc. are different from the actual device, but these are the following explanations and known techniques. The design can be changed as appropriate.

[First Embodiment]
The battery according to the first embodiment will be described with reference to FIGS. A part of the drawing is a perspective view and a developed view, and some members and parts are not shown, but the positive electrode and the negative electrode are configured symmetrically, so the part not shown of one electrode is the other electrode It is revealed from the structure of In addition, the embodiment recognizes that the positive electrode and the negative electrode are configured asymmetrically.

A battery 100 shown in FIG. 1 includes an exterior member 1, an electrode group 2, a positive electrode terminal portion 3, a negative electrode terminal portion 4, and an electrolyte (not shown). A battery 100 shown in FIG. 1 is, for example, a secondary battery. The battery 100 of the embodiment is thin. The thickness of the thin battery 100 is 5 mm or more and 30 mm or less.

As shown in FIGS. 1 and 2 (FIGS. 2A and 2B), the exterior member 1 includes a first exterior portion 5 and a second exterior portion 6. The 1st exterior part 5 is a square tube container with a bottom, and has the flange part 5b in the opening part 5a. In the exterior member 1, the electrode group 2 is accommodated in a space formed by welding the flange portion of the first exterior portion 5 and the second exterior portion 6. 2A is an exploded perspective view seen from the positive electrode side of the battery shown in FIG. 2B is an exploded perspective view seen from the negative electrode side of the battery shown in FIG.

As shown in FIGS. 1, 2, and 5, a recess projecting inward is provided near the center of the corner connecting the short side wall and the bottom of the second exterior part 5, and the bottom of the recess is an inclined surface It is 5d. The second exterior portion 5 has a depth equal to or smaller than the size of the opening 5a (the maximum length of the portion serving as the opening area). The more preferable second exterior portion 5 has a depth equal to or less than the short side of the portion that becomes the opening area (for example, the one shown in FIG. 2). The first exterior portion 5 is, for example, a stainless steel cup-type container having an opening made from a stainless steel plate by shallow drawing. On the other hand, the second exterior portion 6 is a stainless steel lid. The second exterior part 6 covers the opening of the second exterior part 5. Similarly to the second exterior part 5, the second exterior part 6 may be a stainless steel cup-shaped container or plate-like shape made by shallow drawing. The electrode group 2 is housed in a space formed by welding the flange portion 5 b of the first exterior portion 5 to the four sides of the second exterior portion 6. For welding, for example, resistance seam welding is used. Resistance seam welding can achieve high hermeticity and heat resistance at a lower cost than laser welding.

Since it is a thin battery, the space in which the electrode group 2 is accommodated is a low height space. The height of the space in which one electrode group 2 is accommodated is the number of electrode groups 2 accommodated in the exterior member 1 and arranged in the height direction, from the bottom of the first exterior part 5 to the second exterior part. The value obtained by dividing the distance up to 6. Since the battery is thin, the height of the space in which each electrode group 2 is accommodated is 5 mm or more and 30 mm or less. Since the space in which the electrode group 2 is accommodated is a space with a low height, the lead shape is limited.

As shown in FIG. 4, the electrode group 2 has a flat shape, and includes a positive electrode 7, a negative electrode 8, and a separator 9 disposed between the positive electrode 7 and the negative electrode 8. The flat electrode group 2 includes a positive electrode 7, a positive electrode current collecting tab 7 a electrically connected to the positive electrode 7, a negative electrode 8, and a negative electrode current collecting tab 8 a electrically connected to the negative electrode 8. The positive electrode current collecting tab 7a wound on the first end surface is located on the first end surface, and the negative electrode current collecting tab 8a wound on the flat shape is located on the second end surface. One of the two flat surfaces of the electrode group 2 faces the bottom surface of the first exterior part 5, and the other of the two flat surfaces of the electrode group 2 faces the surface of the second exterior part 6. To do.

The positive electrode 7 includes a strip-shaped positive electrode collector made of, for example, a foil, a positive electrode current collector tab 7a having one end parallel to the long side of the positive electrode current collector, and at least the positive electrode current collector tab 7a. And a positive electrode material layer (positive electrode active material-containing layer) 7b formed on the electric body.

On the other hand, the negative electrode 8 is formed by removing, for example, a strip-shaped negative electrode current collector made of foil, a negative electrode current collector tab 8a formed of one end parallel to the long side of the negative electrode current collector, and at least a portion of the negative electrode current collector tab 8a. And a negative electrode material layer (negative electrode active material-containing layer) 8b formed on the negative electrode current collector. In the electrode group 2, the positive electrode material layer 7 b of the positive electrode 7 and the negative electrode material layer 8 b of the negative electrode 8 are opposed to each other through the separator 9, and the positive electrode current collecting tab 7 a is disposed on one side of the winding shaft more than the negative electrode 8 and the separator 9. The positive electrode 7, the separator 9, and the negative electrode 8 are wound in a flat shape so that the negative electrode current collecting tab 8a protrudes from the positive electrode 7 and the separator 9 on the other side. Therefore, in the electrode group 2, the positive electrode current collecting tab 7a wound in a flat spiral shape is located on the first end surface perpendicular to the winding axis.

Further, the negative electrode current collecting tab 8a wound in a flat spiral shape is located on the second end surface perpendicular to the winding axis. The insulating sheet 10 covers a portion between the positive electrode current collector tab 7 a and the negative electrode current collector tab 8 a in the outermost periphery of the electrode group 2. And the insulating sheet 10 has coat | covered the part except the positive electrode current collection tab 7a and the negative electrode current collection tab 8a among the outermost periphery of the electrode group 2. FIG. The electrode group 2 holds an electrolyte (not shown).

The backup positive electrode lead 11 is formed by bending a conductive plate into a U shape. The layers of the positive electrode current collecting tabs 7a are sandwiched between portions (near the center) excluding the curved portions at both ends of the positive electrode current collecting tab 7a. It is in close contact. The electrode group side positive lead 12 is a conductive plate having a larger area than the backup positive lead 11. As shown in FIG. 5, the electrode group-side positive lead 12 has a first extension 12a on the side opposite to the electrode group 2 side. The electrode group side positive lead 12 is connected to the surface of the backup positive lead 11. The backup positive electrode lead 11 is electrically connected to the positive electrode current collecting tab 7 a and the electrode group side positive electrode lead 12. Further, the positive electrode current collecting tab 7 a is electrically connected to the electrode group side positive electrode lead 12. The first extending portion 12 a of the electrode group side positive lead 12 is disposed closer to the electrode group 2 than the first extending portion 23 b of the positive terminal lead 23.

The positive electrode current collecting tab 7a, the backup positive electrode lead 11 and the electrode group side positive electrode lead 12 are integrated by welding, whereby the positive electrode 7 is connected to the electrode group side positive electrode lead 12 via the positive electrode current collecting tab 7a and the backup positive electrode lead 11. Electrically connected. The positive electrode current collecting tab 7a and the backup positive electrode lead 11 are welded by, for example, laser welding or ultrasonic welding. The backup positive electrode lead 11 and the electrode group side positive electrode lead 12 are welded by, for example, laser welding or ultrasonic welding. The backup positive electrode lead 11 can be omitted. When the backup positive electrode lead 11 is omitted, the positive electrode current collecting tab 7a and the electrode side positive electrode lead 12 are preferably welded.

The backup negative electrode lead 13 is formed by bending a conductive plate into a U shape. It is in close contact. The electrode group side negative electrode lead 14 is a conductive plate having a larger area than the backup negative electrode lead 13. As shown in FIG. 6, the electrode group-side negative electrode lead 14 has a first extending portion 14a on the side opposite to the electrode group 2 side. The first extending portion 14 a of the electrode group side negative electrode lead 14 is connected to the surface of the backup negative electrode lead 13. The backup negative electrode lead 13 is electrically connected to the negative electrode current collecting tab 8 a and the electrode group side negative electrode lead 14. Further, the negative electrode current collecting tab 8 a is electrically connected to the electrode group side negative electrode lead 14. The first extending portion 14 a of the electrode group-side negative electrode lead 14 is disposed closer to the electrode group 2 than the first extending portion 36 b of the negative electrode terminal lead 36.

The negative electrode current collecting tab 8a, the backup negative electrode lead 13 and the electrode group side negative electrode lead 14 are integrated by welding, whereby the negative electrode 8 is connected to the electrode group side negative electrode lead 14 via the positive electrode current collecting tab 8a and the backup negative electrode lead 13. Electrically connected. The welding of the negative electrode current collecting tab 8a and the backup negative electrode lead 13 is performed by, for example, laser welding or ultrasonic welding. The backup negative electrode lead 13 and the electrode group side negative electrode lead 14 are welded by, for example, laser welding or ultrasonic welding.

As shown in FIGS. 2 and 5, the positive electrode terminal portion 3 includes a through hole 15 opened in the inclined surface 5 d of the first exterior portion 5, a positive electrode external terminal 17, a positive electrode insulating member 18 a, a positive electrode reinforcing member ( Ring-shaped member) 18b, insulating gasket 19, and positive electrode terminal insulating member 20.

In the positive electrode terminal portion 3, the first exterior portion 5 has a through hole 15 on the positive electrode current collecting tab side. The positive electrode external terminal 17 of the positive electrode terminal portion 3 includes a head portion 21 and a shaft portion extending from the head portion 21. The positive terminal portion 3 includes a positive terminal lead 23 having a through hole 23a. In the positive electrode terminal portion 3, the head portion 21 protrudes outside the first exterior portion 5, the shaft portion is inserted into the through hole 23 a of the positive electrode terminal lead 23, and the shaft portion is the first exterior portion 5 and the positive electrode terminal lead. 23 is fixed by caulking.

As shown in FIG. 5, the burring portion (annular rising portion) 16 extends from the peripheral portion of the through hole 15 toward the inside of the exterior member 1 and is formed by burring.

As shown in FIG. 5, the positive electrode external terminal 17 includes a truncated pyramid-shaped head portion 21 and a columnar shaft portion that penetrates the through hole 15 of the second exterior portion 5. The columnar shaft portion extends from a plane parallel to the top surface of the head 21. The positive external terminal 17 is made of a conductive material such as aluminum or aluminum alloy, for example.

The positive electrode insulating member 18 a insulates the second exterior portion 5 from the positive electrode external terminal 17 and the positive electrode terminal lead 23. The positive electrode reinforcing member 18b is sandwiched between the second exterior portion 5 and the positive electrode insulating member 18a.

The positive electrode reinforcing member 18b is made of, for example, a circular ring made of a material having rigidity higher than that of the gasket. Examples of materials with higher rigidity than gaskets include stainless steel, iron plated (eg, Ni, NiCr, etc.), ceramics, resins with higher rigidity than gaskets (eg, polyphenylene sulfide (PPS), poly Butylene terephthalate (PBT)) and the like. As shown in FIG. 5, the positive electrode reinforcing member 18 b is disposed on the outer peripheral surface of the burring portion 16 and is in contact with the burring portion 16 and the positive electrode insulating member 18 a. Further, when the positive electrode reinforcing member 18b is formed of an insulating material such as resin or ceramics, it can be integrated with the positive electrode terminal insulating reinforcing member 24.

The insulating gasket 19 is a cylindrical body (cylinder part) having a flange part 19a at one opening end. As shown in FIG. 5, the insulating gasket 19 has a cylindrical portion inserted into the through hole 15 and the burring portion 16, and a flange portion 19 a disposed on the outer periphery of the through hole 15 on the outer surface of the first exterior portion 5. Has been. The insulating gasket 19 is, for example, a resin such as fluororesin, fluororubber, polyphenylene sulfide resin (PPS resin), polyether ether ketone resin (PEEK resin), polypropylene resin (PP resin), and polybutylene terephthalate resin (PBT resin). Formed from.

As shown in FIGS. 2 and 5, the positive electrode terminal insulating member 20 is a plate-like member bent at an obtuse angle and has a through hole 20a at the bottom. The positive terminal insulating member 20 is disposed on the outer surface of the first exterior part 5. The flange portion 19 a of the insulating gasket 19 is inserted into the through hole 20 a of the positive terminal insulating member 20.

The positive terminal portion 3 further includes a positive terminal lead 23. The positive terminal lead 23 is a conductive plate having a through hole 23a and a first extension 23b extending to the opening side of the second exterior part 5, that is, the second exterior part 6 side. In FIG. 5, the positive electrode terminal lead 23 has a first extending portion 23 b extending to the electrode group 2 side. The first extension 23b of the positive terminal lead 23 is integrated with the first extension 12a of the electrode group side positive lead 12 by welding. The opposing surfaces of the first extending portion 23b and the first extending portion 12a are welded, and the end surface of the first extending portion 23b on the distal end side and the end surface of the first extending portion 12a are also formed. Welded. At least the tip portion of the first extension 23b of the positive terminal lead 23 and the first extension 12a of the electrode group side positive lead 12 is perpendicular or substantially perpendicular to the surface of the second exterior part 6 (80 ° to 100 °). At least the tip portion of the first extension portion 23 b of the positive electrode terminal lead 23 and the first extension portion 12 a of the electrode group side positive electrode lead 12 is perpendicular or substantially perpendicular to the surface of the second exterior portion 6. Indicates that the lead was not bent after welding of the first extension 23 b of the positive terminal lead 23 and the first extension 12 a of the electrode group side positive lead 12. Although there is an advantage that the wiring of the terminal portion of the electrode can be made compact by bending the lead after welding, it is required to reduce the thickness of the lead in order to bend accurately after welding. However, reducing the thickness of the lead is not preferable in that it is difficult to flow a large current. By making the welded portion face the direction of the surface of the second exterior portion 6, the thickness of the lead can be increased.

Considering the large current characteristics, the thickness of the positive electrode terminal lead 23 can be 0.5 mm or more and 3.0 mm or less, and the thickness of the electrode group side positive electrode lead 12 is 0.5 mm or more and 3.0 mm. It can be as follows. Further, considering the lead bending process and the large current characteristics before welding the leads, the sum of the thickness of the positive terminal lead 23 and the thickness of the electrode group side positive lead 12 is 1.0 mm or more and 1.2 mm or less. It is preferable. These thicknesses are preferably at least filled at the welded portion.

The positive electrode terminal portion 3 further includes a first positive electrode insulation reinforcing member 24. As shown in FIGS. 2 and 5, the first positive electrode insulation reinforcing member 24 includes a main body portion 24a having a structure in which a bottomed rectangular tube is divided in the long side direction, and a circular groove 24b formed in the main body portion 24a. And a through hole 24c opened in the center of the circular groove 24b. The first positive terminal insulation reinforcement member 24 includes a corner portion where the main body portion 24 a is connected to the bottom surface from the short side wall of the first exterior portion 5, and a long side surface from the short side wall of the first exterior portion 5. Cover the corners that lead to Thereby, the 1st exterior part 5, especially the corner vicinity where a short side wall, a long side wall, and a bottom part can be reinforced. A positive electrode insulating member 18a disposed on the outer peripheral surface of the burring portion 16 is disposed in the circular groove 24b. The through hole 24 c communicates with the opening of the burring portion 16 and the through hole 15 of the first exterior portion 5. The positive terminal lead 23 is disposed on the first positive terminal insulation reinforcing member 24. The through hole 23 a of the positive terminal lead 23 communicates with the through hole 24 c of the first positive terminal insulation reinforcing member 24, the opening of the burring portion 16, and the through hole 15 of the first exterior portion 5.

As shown in FIG. 2, the second positive electrode insulation reinforcing member 25 has a structure in which a bottomed rectangular tube is divided in half in the long side direction. The second positive electrode insulation reinforcing member 25 covers about half of the positive electrode current collecting tab 7a from the winding center to the second exterior portion 6 side, whereby the second exterior portion 6, particularly near the short side. Can be reinforced.

The shaft portion of the positive external terminal 17 includes an insulating gasket 19, a through hole 20 a in the positive terminal insulating member 20, a through hole 15 in the first exterior portion 5, a through hole 24 c in the positive terminal insulating reinforcing member 24, and the positive terminal lead 23. After being inserted into the through hole 23a, plastic deformation is caused by caulking. As a result, these members are integrated, and the positive external terminal 17 is electrically connected to the positive terminal lead 23. Therefore, the positive external terminal 17 also serves as a rivet. Note that a boundary portion between the end face of the shaft portion of the positive electrode external terminal 17 and the through hole 23a of the positive electrode terminal lead 23 may be welded with a laser or the like, so that stronger connection and improvement in electrical conductivity may be performed.

2 and 6, the negative electrode terminal portion 4 includes a through hole 30 opened in the inclined surface 5d of the first exterior portion 5, a negative electrode external terminal 32, a negative electrode insulating member 33a, a negative electrode reinforcing member ( Ring-shaped member) 33 b, insulating gasket 34, and negative electrode terminal insulating member 35.

In the negative electrode terminal portion 4, the first exterior portion 5 has a through hole 30 on the negative electrode current collecting tab 8a side. The negative electrode external terminal 32 of the negative electrode terminal portion 4 includes a head portion 21 and a shaft portion extending from the head portion 21. The negative terminal portion 4 includes a negative terminal lead 36 having a through hole 36a. In the negative electrode terminal portion 4, the head portion 21 protrudes outside the first exterior portion 5, the shaft portion is inserted into the through hole 36 a of the negative electrode terminal lead 36, and the shaft portion is the first exterior portion 5 and the negative electrode terminal lead. 36 is fixed by caulking.

As shown in FIG. 6, the burring portion (annular rising portion) 31 extends from the peripheral edge portion of the through hole 31 toward the inside of the exterior member 1 and is formed by burring.

As shown in FIG. 6, the negative electrode external terminal 32 includes a truncated pyramid-shaped head portion 21 and a columnar shaft portion that penetrates the through hole 30 of the second exterior portion 5. The columnar shaft portion extends from a plane parallel to the top surface of the head 21. The negative electrode external terminal 32 is made of a conductive material such as aluminum or an aluminum alloy, for example.

The negative electrode insulating member 33 a insulates the second exterior portion 5 from the negative electrode external terminal 32 and the negative electrode terminal lead 36.
The negative electrode reinforcing member 33b is sandwiched between the second exterior portion 5 and the negative electrode insulating member 33a.

The negative electrode reinforcing member 33b is made of, for example, a circular ring made of a material having rigidity higher than that of the gasket. Examples of materials with higher rigidity than gaskets include stainless steel, iron plated (eg, Ni, NiCr, etc.), ceramics, resins with higher rigidity than gaskets (eg, polyphenylene sulfide (PPS), poly Butylene terephthalate (PBT)) and the like. As shown in FIG. 6, the negative electrode reinforcing member 33 b is disposed on the outer peripheral surface of the burring portion 31 and is in contact with the burring portion 31 and the negative electrode insulating member 33 a. Further, when the negative electrode reinforcing member 33b is formed of an insulating material such as resin or ceramics, it can be integrated with the terminal insulating reinforcing member 37.

The insulating gasket 34 is a cylindrical body (cylinder part) having a flange part at one open end. As shown in FIGS. 2 and 6, the insulating gasket 34 has a cylindrical portion inserted into the through hole 30 and the burring portion 31, and a flange portion that is the outer periphery of the through hole 30 on the outer surface of the first exterior portion 5. Is arranged. The insulating gasket 34 is, for example, a resin such as fluororesin, fluororubber, polyphenylene sulfide resin (PPS resin), polyetheretherketone resin (PEEK resin), polypropylene resin (PP resin), and polybutylene terephthalate resin (PBT resin). Formed from.

As shown in FIGS. 2 and 6, the negative electrode terminal insulating member (third negative electrode insulating member) 35 is a plate-like member bent at an obtuse angle and has a through hole at the bottom. The negative terminal insulating member 35 is disposed on the outer surface of the first exterior portion 5. The flange portion of the insulating gasket 34 is inserted into the through hole of the negative electrode terminal insulating member 35.

The negative terminal portion 4 further includes a negative terminal lead 36 (first negative lead). The negative electrode terminal lead 36 is a conductive plate having a through hole 36 a and a first extending portion 36 b extending to the opening side of the first exterior portion 5, that is, the second exterior portion 6 side. In FIG. 6, the negative terminal lead 36 has a first extending portion 36 b extending to the electrode group 2 side. The first extension 36b of the negative terminal lead 36 is integrated with the first extension 14a of the electrode group side negative lead 14 by welding. The opposing surfaces of the first extending portion 36b and the first extending portion 14a are welded, and the end surface of the first extending portion 36b on the distal end side and the end surface of the first extending portion 14a are also formed. Welded. At least the tip portion of the first extension portion 36b of the negative electrode terminal lead 36 and the first extension portion 14a of the electrode group side negative electrode lead 14 is perpendicular or substantially perpendicular to the surface of the second exterior portion 6 (80 ° to 100 °). At least the tip portion of the first extension part 36 b of the negative electrode terminal lead 36 and the first extension part 14 a of the electrode group side negative electrode lead 14 is perpendicular or substantially perpendicular to the surface of the second exterior part 6. Represents that the lead was not bent after welding of the first extending portion 36b of the negative electrode terminal lead 36 and the first extending portion 14a of the electrode group side negative electrode lead 14. Although there is an advantage that the wiring of the terminal portion of the electrode can be made compact by bending the lead after welding, it is required to reduce the thickness of the lead in order to bend accurately after welding. However, reducing the thickness of the lead is not preferable in that it is difficult to flow a large current. By making the welded portion face the direction of the surface of the second exterior portion 6, the thickness of the lead can be increased.

Considering the large current characteristics, the thickness of the negative electrode terminal lead 36 can be 0.5 mm or more and 3.0 mm or less, and the thickness of the electrode group side negative electrode lead 14 is 0.5 mm or more and 3.0 mm. It can be as follows. Furthermore, considering the lead bending process and the large current characteristics before welding the leads, the sum of the thickness of the negative electrode terminal lead 36 and the thickness of the electrode group side negative electrode lead 14 is 1.0 mm or more and 1.2 mm or less. It is preferable.

The negative electrode terminal portion 4 further includes a first negative electrode terminal insulation reinforcing member 37. As shown in FIG. 2, the first negative electrode terminal insulation reinforcing member 37 includes a main body portion 37a having a structure in which a bottomed rectangular tube is divided in the long side direction, a circular groove 37b formed in the main body portion 37a, and a circular shape. And a through hole 37c opened in the center of the groove 37b. The first negative electrode terminal insulation reinforcing member 37 includes a corner portion where the main body portion 37 a is connected to the bottom surface from the short side wall of the first exterior portion 5, and the long side surface from the short side wall of the first exterior portion 5. Cover the corners that lead to Thereby, the 1st exterior part 5, especially the corner vicinity where a short side wall, a long side wall, and a bottom part can be reinforced. A negative electrode insulating member 33 a disposed on the outer peripheral surface of the burring portion 31 is disposed in the circular groove 37 b. The through hole 37 c communicates with the opening of the burring portion 31 and the through hole 30 of the first exterior portion 5. A negative terminal lead 36 is disposed on the first negative terminal insulation reinforcing member 37. The through hole 36 a of the negative electrode terminal lead 36 communicates with the through hole 37 c of the first negative electrode terminal insulating reinforcing member 37, the opening of the burring portion 31 and the through hole 30 of the first exterior portion 5.

As shown in FIG. 2, the second negative electrode insulation reinforcing member 38 has a structure in which a bottomed rectangular tube is divided in half in the long side direction. The second negative electrode insulation reinforcing member 38 covers about half of the negative electrode current collecting tab 8a from the winding center to the second exterior portion 6 side. Thereby, the 2nd exterior part 6, especially the short side vicinity can be reinforced.

The shaft portion of the negative external terminal 32 includes an insulating gasket 34, a through hole 35a in the negative terminal insulating member 35, a through hole 30 in the first exterior portion 5, a through hole 37c in the first negative terminal insulating reinforcing member 37, and a negative terminal. After being inserted into the through hole 36a of the lead 36, plastic deformation is caused by caulking. As a result, as shown in FIGS. 2, 6, and 7, these members are integrated and the negative external terminal 32 is electrically connected to the negative terminal lead 36. Therefore, the negative external terminal 36 also serves as a rivet. Note that a boundary portion between the end face of the shaft portion of the negative electrode external terminal 32 and the through hole 36a of the negative electrode terminal lead 36 may be welded with a laser or the like, so that stronger connection and electrical conductivity can be improved.

The backup positive terminal lead 11, the electrode group side positive lead 12, the positive terminal lead 23, the backup negative terminal lead 13, the electrode group side negative lead 14 and the negative terminal lead 36 can be made of, for example, aluminum or an aluminum alloy material. . In order to reduce the contact resistance, the material of the lead is preferably the same as the material of the positive electrode current collector or the negative electrode current collector that can be electrically connected to the lead.

The positive insulating member 18a, the first positive insulating reinforcing member 24, the second positive insulating reinforcing member 25, the negative insulating member 33a, the first negative terminal insulating reinforcing member 37, and the second negative insulating reinforcing member 38 are, for example, Tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), polypropylene (PP), polyethylene (PE), nylon, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), It is formed from a thermoplastic resin such as polyphenylene sulfide (PPS) and polyetheretherketone (PEEK).

The electrode group 2 is housed in the first exterior part 5 so that the first end face 7 a faces the positive terminal part 3 and the second end face 8 a faces the negative terminal part 4. Therefore, the plane intersecting the first end surface 7a and the second end surface 8a of the electrode group 2 faces the bottom surface 5c in the first exterior portion 5, and the curved surface intersecting the first end surface 7a and the second end surface 8a is the first. It faces the long side surface in the exterior part 5.

In the corner portion connecting the short side wall and the bottom of the first exterior portion 5, there are gaps between the first end surface 7a of the electrode group 2 and the second end surface 8a. By providing a concave portion projecting inward at a corner portion connecting the short side wall and the bottom portion of the first exterior portion 5 and forming the bottom portion of the concave portion as an inclined surface 5d, the dead space in the first exterior portion 5 is reduced. Therefore, the volume energy density of the battery can be increased. Further, by disposing the positive electrode terminal portion 3 and the negative electrode terminal portion 4 on each of the inclined surfaces 5d, the terminal portions are installed rather than the case where the positive electrode terminal portion 3 and the negative electrode terminal portion 4 are provided on the short side surface having no inclined surface. The area can be increased. Therefore, the diameter of the shaft portion of the positive electrode external terminal 17 and the shaft portion of the negative electrode external terminal 32 can be increased, so that a large current (high rate current) can flow with low resistance.

As a result of the electrode group 2 being housed in the first exterior portion 5, a bottomed rectangular cylindrical shape formed by contacting the lower end of the second positive electrode insulation reinforcing member 25 with the upper end of the first positive electrode insulation reinforcing member 24. The positive electrode current collecting tab 7a is covered with a cover. Further, the negative electrode current collecting tab 8 a is covered with a bottomed rectangular cylindrical cover formed by contacting the lower end of the second negative electrode insulating reinforcing member 38 with the upper end of the first negative electrode insulating reinforcing member 37.

The second exterior part 6 functions as a lid for the first exterior part 5. The electrode group 2 is sealed in the exterior member 1 by welding the four sides of the flange portion 5 b of the first exterior portion 5 and the second exterior portion 6.

The battery shown in FIGS. 1 to 7 described above has electrodes in a space formed by welding a stainless steel first exterior part having a flange part in the opening and a stainless steel second exterior part. It is preferable that the exterior member in which a group is accommodated is included. Since the second exterior part 5 and the second exterior part 6 are made of stainless steel, high strength can be maintained even when the plate thickness of the first and second exterior parts is reduced. As a result, since the flexibility of the exterior member can be increased, the electrode group 2 can be easily restrained by applying a load from the outside of the reduced pressure seal or the exterior member 1. Thereby, the distance between the electrodes of the electrode group 2 can be stabilized and the resistance can be lowered, and the battery pack having vibration resistance and impact resistance can be easily realized. Furthermore, if the flexibility of the second exterior part 5 and the second exterior part 6 is high, it is easy to reduce the distance from the inner surfaces of the first and second exterior parts to the electrode group. Can improve sex.

The second exterior part 5 and the second exterior part 6 made of stainless steel are easy to weld and can be sealed by inexpensive resistance seam welding. Therefore, it is possible to realize an exterior member having a higher gas sealing property than a laminate film container at a low cost. Moreover, the heat resistance of the exterior member can be improved. For example, SUS304 has a melting point of 1400 ° C., whereas Al has a melting point of 650 ° C.

Also, the shaft portion of the external terminal is plastically deformed as a result of being caulked and fixed in the through hole. As a result, a force is applied in the radial direction of the insulating gasket. However, since the burring portion is reinforced by the ring-shaped member disposed on the outer side, a compressive stress is generated in the insulating gasket, and the external terminal is connected to the first exterior portion 5. Can be connected with high strength. Even if the plate thickness of the first exterior portion 5, that is, the plate thickness of the burring portion is reduced, the ring-shaped member can reinforce the burring portion. Can be connected to the first exterior portion 5 with high strength. Furthermore, since the burring portion extends from the edge of the through hole toward the inside of the exterior member 1, it is possible to suppress liquid leakage when the internal pressure of the exterior member 1 increases due to gas generation or the like by the action of the external pressure. It becomes. Therefore, high reliability can be achieved even when the plate thickness of the first exterior portion 5 and the second exterior portion 6 is reduced.

Therefore, according to the battery of the first embodiment, high strength and reliability can be obtained even when the plate thickness of the first exterior portion 5 and the second exterior portion 6 is reduced. A battery having excellent heat dissipation and high strength and reliability can be provided.

When the first exterior part 5 has a depth equal to or less than the maximum length of the opening part, the opening area of the first exterior part 5 is widened. The second exterior part is welded to the four sides of the first exterior part, but as the opening area increases, the length of one side to be welded increases, so the three sides are welded first and the remaining one side It becomes easy to inject the electrolyte from the gap. Moreover, since the exterior member 1 can be temporarily sealed by providing a location where the welding strength is lower than the others, a temporary sealing component (for example, a rubber plug) can be made unnecessary. Furthermore, since the exterior member 1 has a flat shape, the heat dissipation of the battery can be improved.

The dead space in the 1st exterior part 5 can be reduced by the 1st exterior part 5 including the recessed part which has the inclined surface 5d, and arrange | positioning a terminal part in the inclined surface 5d.

In addition, the inclined surface 5d is not limited to the one provided near the center of the short side of the exterior member 1, and may extend over the entire short side of the exterior member.

It is desirable to further include a second lead electrically connected to the positive electrode current collecting tab or the negative electrode current collecting tab, and to electrically connect the second lead to the first lead. Thereby, positioning at the time of welding becomes easy. Further, even if the position of the first lead with respect to the positive electrode current collecting tab and the negative electrode current collecting tab is slightly shifted, a sufficient connection area can be ensured, so that a low resistance battery can be realized.

The first end surface of the external terminal has a quadrangular top surface and first and second inclined surfaces connected to two opposite sides of the top surface, so that any one of the three surfaces is welded. The welding direction can be changed by selecting the surface.

The plate thickness of the first exterior part and the second exterior part is preferably in the range of 0.02 mm to 0.3 mm. By setting it within this range, the conflicting properties of mechanical strength and flexibility can be achieved. A more preferable range of the plate thickness is 0.05 mm or more and 0.15 mm or less.

The difference (wall thickness) between the outer and inner diameters of the positive electrode terminal portion 3, the negative electrode terminal portion 4, or both of the ring-shaped members is preferably equal to or greater than the plate thickness of the first exterior portion 5. Thereby, irrespective of the plate | board thickness of a 1st exterior part, an external terminal can be connected to a 1st exterior part with high intensity | strength. Specifically, the shortest thickness can be 0.1 mm or more.

Also, the outer shape of the ring-shaped member is not necessarily the same shape as the burring cross-sectional shape, and may be a polyhedron such as a rectangle or a hexagon, or may be a composite shape of a single or a plurality of curves and a single or a plurality of straight lines.

A flat plate as illustrated in FIG. 5 and FIG. 6 can be used for the second exterior portion 6, but a plate having a flange portion at the opening may be used instead of the flat plate. As an example of such a structure, the same thing as the 1st exterior part 5 can be mentioned.

The backup positive electrode lead 11 and the backup negative electrode lead 13 are not limited to U-shaped conductive plates, and conductive flat plates may be used. It is also possible to employ a configuration in which the backup positive electrode lead 11 and / or the backup negative electrode lead 13 are not used.

The exterior member can further include a safety valve or the like that can release the pressure inside the battery when the internal pressure of the battery rises above a specified value.

The battery according to the first embodiment may be a primary battery or a secondary battery. An example of the battery according to the first embodiment is a lithium ion secondary battery.

The positive electrode, negative electrode, separator, and nonaqueous electrolyte of the battery according to the first embodiment will be described below.

1) Positive Electrode The positive electrode can include, for example, a positive electrode current collector, a positive electrode material layer held on the positive electrode current collector, and a positive electrode current collector tab. The positive electrode material layer can include, for example, a positive electrode active material, a conductive agent, and a binder.

As the positive electrode active material, for example, an oxide or a sulfide can be used. Examples of oxides and sulfides include manganese dioxide (MnO ₂ ) that occludes lithium, iron oxide, copper oxide, nickel oxide, lithium manganese composite oxide (eg, Li _x Mn ₂ O ₄ or Li _x MnO ₂ ), Lithium nickel composite oxide (for example, Li _x NiO ₂ ), lithium cobalt composite oxide (for example, Li _x CoO ₂ ), lithium nickel cobalt composite oxide (for example, LiNi _1-y Co _y O ₂ ), lithium manganese cobalt composite oxide (e.g. _{_{_{Li x Mn y Co 1-y}}} O 2), lithium manganese nickel complex oxide having a spinel structure (e.g., _{_{_{Li x Mn 2-y Ni y}}} O 4), lithium phosphates having an olivine structure (e.g., Li _x _{_{_{FePO 4, Li x Fe 1-}}} y Mn y PO 4, Li x CoPO 4), iron sulfate _{_{_{(Fe 2 (SO 4) 3}}} ), vanadium oxides (e.g. Examples thereof include V ₂ O ₅ ) and lithium nickel cobalt manganese composite oxide. In the above formula, 0 <x ≦ 1 and 0 <y ≦ 1. As the active material, these compounds may be used alone, or a plurality of compounds may be used in combination.

The binder is blended to bind the active material and the current collector. Examples of the binder include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), and fluorine-based rubber.

The conductive agent is blended as necessary in order to enhance the current collecting performance and suppress the contact resistance between the active material and the current collector. Examples of the conductive agent include carbonaceous materials such as acetylene black, carbon black, and graphite.

In the positive electrode material layer, the positive electrode active material and the binder are preferably blended at a ratio of 80% by mass to 98% by mass and 2% by mass to 20% by mass, respectively.

A sufficient electrode strength can be obtained by setting the binder to an amount of 2% by mass or more. Moreover, the content of the insulating material of an electrode can be reduced by setting it as 20 mass% or less, and internal resistance can be reduced.

When a conductive agent is added, the positive electrode active material, the binder, and the conductive agent are 77% by mass or more and 95% by mass or less, 2% by mass or more and 20% by mass or less, and 3% by mass or more and 15% by mass or less, respectively. It is preferable to mix | blend in a ratio. The conductive agent can exhibit the above-described effects by adjusting the amount to 3% by mass or more. Moreover, by setting it as 15 mass% or less, decomposition | disassembly of the nonaqueous electrolyte on the surface of the positive electrode conductive agent under high temperature storage can be reduced.

The positive electrode current collector is preferably an aluminum foil or an aluminum alloy foil containing at least one element selected from Mg, Ti, Zn, Ni, Cr, Mn, Fe, Cu and Si.

The positive electrode current collector is preferably integral with the positive electrode current collecting tab. Alternatively, the positive electrode current collector may be a separate body from the positive electrode current collector tab.

2) Negative electrode A negative electrode can contain the negative electrode collector, the negative electrode material layer hold | maintained at the negative electrode collector, and the negative electrode current collection tab, for example. The negative electrode material layer can include, for example, a negative electrode active material, a conductive agent, and a binder.

As the negative electrode active material, for example, a metal oxide, metal nitride, alloy, carbon, or the like that can occlude and release lithium ions can be used. It is preferable to use as the negative electrode active material a material capable of inserting and extracting lithium ions at a potential of 0.4 V or higher (vs. Li / Li ⁺ ).

Examples of the negative electrode active material include graphite materials or carbonaceous materials (for example, graphite, coke, carbon fiber, spherical carbon, pyrolytic vapor phase carbonaceous material, resin fired body, etc.), chalcogen compounds (for example, titanium disulfide, Molybdenum disulfide, niobium selenide, etc.), light metal (eg, aluminum, aluminum alloy, magnesium alloy, lithium, lithium alloy, etc.), Li _{4 + x} Ti ₅ O ₁₂ (x is in the range of −1 ≦ x ≦ 3 due to charge / discharge reaction) Spinel type lithium titanate, ramsteride type Li _{2 + x} Ti ₃ O ₇ (x varies in the range of −1 ≦ x ≦ 3 by charge / discharge reaction), Ti and P, V, Sn Metal composite oxides and niobium titanium composite oxides containing at least one element selected from the group consisting of Cu, Ni and Fe And the like.

Examples of the metal composite oxide containing at least one element selected from the group consisting of Ti and P, V, Sn, Cu, Ni and Fe include TiO ₂ -P ₂ O ₅ and TiO ₂ -V _2. O ₅ , TiO ₂ —P ₂ O ₅ —SnO ₂ , TiO ₂ —P ₂ O ₅ —MO (M is at least one element selected from the group consisting of Cu, Ni and Fe). These metal composite oxides change to lithium titanium composite oxides when lithium is inserted by charging. It is preferable to include one or more substances selected from the group consisting of lithium titanium oxide (for example, spinel type lithium titanate), silicon and tin. The binder for the negative electrode active material layer is the same as the binder for the positive electrode active material layer. The conductive agent of the negative electrode active material layer is the same as the conductive agent of the positive electrode active material layer.

Examples of the composite oxide containing niobium titanium include, for example, the general formula Li _a TiM _b Nb _{2 ± β} O _{7 ± σ} (where each subscript value is 0 ≦ a ≦ 5, 0 ≦ b ≦ 0.3, 0 ≦ β ≦ 0.3, 0 ≦ σ ≦ 0.3, and M is at least one selected from the group consisting of Fe, V, Mo, and Ta (one or more). A compound oxide having a monoclinic crystal structure represented by the general formula Li _{2 + a1} M (I) _2-b1 Ti _6-c1 M (II) _d1 O _{14 + σ1} (where, The value of each subscript is in the range of 0 ≦ a1 ≦ 6, 0 <b1 <2, 0 <c1 <6, 0 <d1 <6, −0.5 ≦ σ1 ≦ 0.5, and M (I) Is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs and K (may be one or more), and M (II) is Zr, Sn, V, Nb, Ta, Mo, An orthorhombic crystal structure represented by at least one selected from the group consisting of W, Fe, Co, Mn, and Al (including one or more and Nb). A composite oxide having the following can be used. In the above general formula Li _{2 + a1} M (I) _2-b1 Ti _6-c1 M (II) _d1 O _{14 + σ1} , the values of the subscripts are 0 ≦ a1 ≦ 6, 0 <b1 <2, 0 <c1 <6, 0 <d1 <6, −0.5 ≦ σ1 ≦ 0.5, and M (I) is at least selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs and K. 1 type (may be 1 type or multiple types), and M (II) is Nb, or Nb and Zr, Sn, V, Ta, Mo, W, Fe, Co, Mn and It is preferably a combination with at least one selected from the group consisting of Al (one or more). In particular, monoclinic niobium titanium-containing composite oxides are more desirable because they have a large capacity per weight and can increase battery capacity.

The conductive agent is blended in order to enhance the current collecting performance and suppress the contact resistance between the negative electrode active material and the current collector. Examples of the conductive agent include carbonaceous materials such as acetylene black, carbon black, and graphite.

The binder is blended to fill a gap between the dispersed negative electrode active materials and to bind the negative electrode active material and the current collector. Examples of the binder include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), fluorine-based rubber, and styrene butadiene rubber.

The active material, the conductive agent, and the binder in the negative electrode material layer are blended at a ratio of 68% by mass to 96% by mass, 2% by mass to 30% by mass, and 2% by mass to 30% by mass, respectively. It is preferable. By setting the amount of the conductive agent to 2% by mass or more, the current collecting performance of the negative electrode layer can be improved. Further, by setting the amount of the binder to 2% by mass or more, the binding property between the negative electrode material layer and the current collector can be sufficiently exhibited, and excellent cycle characteristics can be expected. On the other hand, the conductive agent and the binder are each preferably 28% by mass or less in order to increase the capacity.

As the current collector, a material that is electrochemically stable at the lithium insertion / release potential of the negative electrode active material is used. The current collector is preferably made of copper, nickel, stainless steel or aluminum or an aluminum alloy containing at least one element selected from Mg, Ti, Zn, Mn, Fe, Cu and Si. The thickness of the current collector is preferably in the range of 5 to 20 μm. A current collector having such a thickness can balance the strength and weight reduction of the negative electrode.

The negative electrode current collector is preferably integral with the negative electrode current collecting tab. Alternatively, the negative electrode current collector may be a separate body from the negative electrode current collection tab.

For example, the negative electrode is prepared by suspending a negative electrode active material, a binder and a conductive agent in a commonly used solvent to prepare a slurry, and applying this slurry to a current collector and drying to form a negative electrode material layer It is produced by applying a press. The negative electrode may also be produced by forming a negative electrode active material, a binder, and a conductive agent in the form of a pellet to form a negative electrode material layer, which is disposed on a current collector.

3) Separator A porous and thin insulating thin film. As a separator, a nonwoven fabric, a film, paper, an inorganic particle layer, etc. are contained. Examples of the constituent material of the separator include polyolefins such as polyethylene and polypropylene, cellulose, polyester, polyvinyl alcohol, polyimide, polyamide, polyamideimide, polytetrafluoroethylene, and vinylon. Non-woven fabrics containing cellulose fibers can be cited as examples of preferred separators from the viewpoint of thinness and mechanical strength. The inorganic particle layer includes oxide particles, a thickener, and a binder. Metal oxides such as aluminum oxide, titanium oxide, magnesium oxide, zinc oxide, and barium sulfate can be used for the oxide particles. Carboxymethylcellulose can be used as the thickener. As the binder, methyl acrylate, an acrylic copolymer containing the same, styrene butadiene rubber (SBR), or the like can be used. The insulating sheet 10 may use a nonwoven fabric, a film, or paper as in the case of the separator 9. It is preferable that the insulating sheet 10 is further fixed with a tape (not shown).

4) Electrolyte The electrolyte is a solution containing an electrolyte salt and a non-aqueous solvent, a non-aqueous gel electrolyte obtained by combining a polymer material in a solution containing an electrolyte salt and a non-aqueous solvent, a solution containing an electrolyte salt and water, or an electrolyte salt. It is preferable to use a water-based gel electrolyte obtained by combining a polymer material with a solution containing water.

The electrolyte salt contained in the non-aqueous solution is, for example, LiPF ₆ , LiBF ₄ , Li (CF ₃ SO ₂ ) ₂ N (bistrifluoromethanesulfonylamide lithium; commonly known as LiTFSI), LiCF ₃ SO ₃ (commonly known as LiTFS), Li (C _{_{_{_{2 F 5 SO 2) 2 N}}}} ( bis pentafluoroethanesulfonyl amide lithium; called _{_{_{LiBETI), LiClO 4, LiAsF 6}}} , LiSbF 6, LiB (C 2 O 4) 2 ( bis oxa Lato lithium borate; called LiBOB), difluoro Lithium such as (trifluoro-2-oxide-2-trifluoro-methylpropionate (2-)-0,0), LiBF ₂ OCOOC (CF ₃ ) ₂ (lithium borate; commonly known as LiBF ₂ (HHIB)) A salt can be used. These electrolyte salts may be used alone or in combination of two or more. In particular, LiPF ₆ and LiBF ₄ are preferable. As the lithium salt, a supporting salt that conducts ions can be used. For example, lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate, an imide-based support salt, and the like can be given. The lithium salt may contain one type or two or more types.

The non-aqueous electrolyte salt concentration is preferably in the range of 0.5 mol / L to 3 mol / L, and more preferably in the range of 0.7 mol / L to 2 mol / L. Such regulation of the electrolyte concentration makes it possible to further improve the performance when a high load current is passed while suppressing the influence of an increase in viscosity due to an increase in the electrolyte salt concentration.

The non-aqueous solvent is not particularly limited, and examples thereof include cyclic carbonates such as propylene carbonate (PC) and ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), and methyl ethyl carbonate (MEC). Alternatively, linear carbonate such as dipropyl carbonate (DPC), 1,2-dimethoxyethane (DME), γ-butyrolactone (GBL), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2-MeHF), 1,3-dioxolane , Sulfolane, acetonitrile (AN) can be used. These solvents may be used alone or in combination of two or more. A non-aqueous solvent containing a cyclic carbonate and / or a chain carbonate is preferred. Examples of the polymer material contained in the non-aqueous gel electrolyte include polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyethylene oxide (PEO), and polymethacrylate.

The electrolyte salt contained in the aqueous solution is LiCl, LiBr, LiOH, Li ₂ SO ₄ , LiNO ₃ , LiN (SO ₂ CF ₃ ) ₂ (lithium trifluoromethanesulfonylamide; commonly known as LiTFSA), LiN (SO ₂ C ₂ F ₅ ) ₂ (lithium bispentafluoroethanesulfonylamide; commonly known as LiBETA), LiN (SO ₂ F) ₂ (lithium bisfluorosulfonylamide; commonly known as LiFSA), LiB [(OCO) ₂ ] _{2 and the} like. The kind of lithium salt to be used can be one kind or two or more kinds. Examples of the polymer material contained in the aqueous gel electrolyte include polyvinylidene fluoride (PVdF), polyacrylonitrile (PAN), polyethylene oxide (PEO), and polymethacrylate.

The aqueous electrolyte salt concentration is preferably from 1 mol / L to 12 mol / L, more preferably from 112 mol / L to 10 mol / L. In order to suppress electrolysis of the electrolytic solution, LiOH or Li ₂ SO ₄ can be added to adjust the pH. The pH value is preferably from 3 to 13, more preferably from 4 to 12.

Alternatively, as the non-aqueous electrolyte, a room temperature molten salt (ionic melt) containing lithium ions, a polymer solid electrolyte, an inorganic solid electrolyte, or the like may be used.

“Room temperature molten salt (ionic melt)” refers to a compound that can exist as a liquid at room temperature (15 to 25 ° C.) among organic salts composed of a combination of an organic cation and an anion. The room temperature molten salt includes a room temperature molten salt that exists alone as a liquid, a room temperature molten salt that becomes liquid when mixed with an electrolyte, and a room temperature molten salt that becomes liquid when dissolved in an organic solvent. In general, the melting point of a room temperature molten salt used for a nonaqueous electrolyte battery is 25 ° C. or less. The organic cation generally has a quaternary ammonium skeleton.

The battery manufacturing method according to the first embodiment will be described below. FIG. 8A to FIG. 8B and FIG. 9A to FIG. 9D show process steps for manufacturing a battery.

The electrode group 2 with the insulating sheet 10 as illustrated in FIG. Moreover, the 1st exterior part 5 to which the positive electrode terminal part 3 and the negative electrode terminal part 4 were fixed as illustrated in FIG. 7 is produced. Note that at least one guide hole for positioning is opened in each of the first exterior part 5 and the second exterior part 6. An example is shown in FIGS. 8 (a) and 8 (b). FIG. 8A shows an example in which positioning guide holes 39 are opened at the four corners of the second exterior portion 6. FIG. 8B shows an example in which positioning guide holes 39 are opened at the four corners of the first exterior portion 5.

The electrode group 2 is housed in the first exterior portion 5, the electrode group side positive lead 12 is joined to the positive terminal lead 23 by welding or the like, and the electrode group side negative lead 14 is welded to the negative terminal lead 36. And join. For joining, for example, laser welding, TIG welding, or friction stir welding can be used. In the embodiment, any joining is handled as welding.

Next, the second positive electrode insulation reinforcing member 25 and the second negative electrode insulation reinforcing member 38 are placed on the positive electrode current collecting tab 7a and the negative electrode current collecting tab 8a of the electrode group 2. Subsequently, the second exterior part 6 is arranged on the first exterior part 5. Since the guide holes 39 are opened at the four corners of each of the first exterior part 5 and the second exterior part 6, it is easy to determine the position of the second exterior part 6 with respect to the first exterior part 5.

Next, as shown in FIG. 9A, the three sides (for example, the long side and the two short sides) of the first exterior part 5 and the second exterior part 6 are welded. For welding, for example, resistance seam welding is used. The weld location is indicated by reference numeral 40. It is desirable that the welding location 40 be located inside the outer edges of the first exterior part 5 and the second exterior part 6.

After injecting the electrolytic solution from the opening on one side of the unwelded side, this one side is welded by, for example, resistance seam welding as shown in FIG. It is desirable that the welding location 41 be an outer edge portion of the first exterior portion 5 and the second exterior portion 6.

Next, after performing aging and initial charge / discharge, as shown in FIG. 9C, a part of the welded part 41 is cut off to form a cutout part 42, and the gas in the exterior member is released. Then, as shown in FIG.9 (d), the welding location (long side of the 2nd exterior part 6) 43 further inside than the welding location 41 is welded by resistance seam welding etc. As shown in FIG. This welding is desirably performed in a reduced pressure atmosphere.

Then, if necessary, the guide hole 39 can be removed by cutting the vicinity of the outer edges of the first exterior part 5 and the second exterior part 6. The guide hole 39 may be left.

By the method described above, the battery of the first embodiment can be manufactured with high productivity.

The battery according to the first embodiment can include a plurality of electrode groups in one exterior member. In this case, as the second exterior part, it is desirable to use the one having a flange part at the opening, similarly to the first exterior part.

When a plurality of electrode groups are stored in one exterior member, the plurality of electrode groups can be connected in series or in parallel. FIGS. 10A to 10D are process diagrams on the positive electrode side for manufacturing a battery configuration in which a plurality (two) of electrode groups are connected in parallel. FIG. 10D shows the created battery 101. A plurality of electrode groups 2 are prepared, and the central tip of the positive electrode current collecting tab 7 a is bundled with the backup positive electrode lead 11. Next, the backup positive electrode lead 11 and the electrode group side positive electrode lead 12 are welded. After welding, the electrode group side positive lead 12 is bent to form the first extension portion 12 as shown in FIG. 10B. Alternatively, the electrode-side positive lead bent in advance may be welded to the backup positive lead 11 to obtain a member as shown in FIG. 10B.

Then, the member shown in FIG. 10B is inserted from the opening side of the first exterior member 5 in which the positive electrode terminal portion 3 is previously incorporated. After the insertion, the first extended portion 12a of the electrode group side positive lead 12 and the first extended portion of the positive terminal lead 23 are fixed by laser welding, so that one electrode group 2 becomes the first as shown in FIG. 10C. 1 is fixed in the exterior portion 5. Similarly, the other electrode group 2 is inserted into the first exterior portion 5, laser welding is performed, and the second exterior portion 6 is covered to accommodate the plurality of electrode groups 2 shown in FIG. 10D. Battery 101 can be obtained. By changing the direction of the electrodes of the plurality of electrode groups, series connection can be achieved.

FIG. 11 shows a positive electrode part (FIG. 11A) and a negative electrode part (FIG. 11B) of a battery 102 which is a modification of the battery 100 of the first embodiment. The negative electrode portion shown in FIG. 11B is configured symmetrically with the positive electrode portion of FIG. 11A. In the battery 102 of FIGS. 11A and 11B, the positive terminal lead 23 has a second extending portion 23c, and the negative terminal lead 36 has a second extending portion 36c. The second extending

portions

23c and 36c support the positive electrode current collecting tab 7a, the negative electrode current collecting tab 8a, the backup positive electrode lead 11 and the backup negative electrode lead 13 in physical contact with each other. The positive electrode current collecting tab 7a or the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7a is sandwiched between the second extending portion 23c of the positive electrode terminal lead 23 and the electrode group side positive electrode lead 12. The second extension 23c of the positive terminal lead 23 supports the side of the positive current collecting tab 7a opposite to the side where the electrode group side positive lead 12 is present. A backup negative electrode lead 13 sandwiching the negative electrode current collecting tab 8a or the negative electrode current collecting tab 8a is sandwiched between the second extending portion 36c of the negative electrode terminal lead 36 and the electrode group side negative electrode lead 14. The second extending portion 36c of the negative electrode terminal lead 36 supports the side of the negative electrode current collecting tab 8a opposite to the side where the electrode group side negative electrode lead 14 is present. The second extending

portions

23c and 36c are not welded to the positive electrode current collecting tab 7a, the negative electrode current collecting tab 8a, the backup positive electrode lead 11, and the backup negative electrode lead 13. When the current collecting tab portion is supported by the second extending

portions

23c and 36c, the structure is stabilized. Moreover, it is also preferable in that the positioning accuracy between the leads is improved. It is preferable from the viewpoint of positioning and stability that the second extending

portions

23c and 36c are provided at any one of the central portion, both ends, and the whole of the positive electrode terminal lead 23 and the negative electrode terminal lead 36. Therefore, such a modification can be easily manufactured, has excellent lead portion stability, and can provide a battery suitable for large currents.

FIG. 12 shows a positive electrode portion of a battery 103 which is a modification of the battery 102 of the first embodiment. The negative electrode side is configured symmetrically with the positive electrode side and is not shown. The difference between the battery 103 and the battery 102 is that the positive electrode current collecting tab 7a or the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7a and the second extending portion 23c of the positive electrode terminal lead 23 are the electrode group side positive electrode lead 12. And the electrode group side positive lead 12 is sandwiched between the negative electrode current collecting tab 8a or the backup negative electrode lead 13 sandwiching the negative electrode current collecting tab 8a and the second extending portion 36c of the negative electrode terminal lead 36. It is.
The second extending

portions

23c and 36c are not welded to the positive electrode current collecting tab 7a, the negative electrode current collecting tab 8a, the backup positive electrode lead 11 and the backup negative electrode lead 13. When the current collecting tab portion is supported by the second extending

portions

FIG. 13A shows a positive electrode portion of a battery 104 which is a modification of the battery 100 of the first embodiment. FIG. 13B shows the negative electrode portion of the battery 103. The negative electrode part of FIG. 13B is configured symmetrically with the positive electrode part of FIG. 13A. In the battery 103 of FIGS. 13A and 12B, the first extension 23b of the positive electrode terminal lead 23 and the first extension 12a of the electrode group side positive lead 12 are fitted, and the first extension of the negative terminal lead 36 is obtained. The portion 36b and the first extending portion 14a of the electrode group side negative electrode lead 14 are fitted. On the positive electrode side, the concave portion 12b of the electrode group side positive electrode lead 12 and the convex portion 23d of the positive electrode terminal lead 23 are fitted, so that positioning is facilitated and the connection by welding is strengthened, and the stability of the connection is improved. is doing. On the negative electrode side, the concave portion 14b of the electrode group-side negative electrode lead 14 and the convex portion 36d of the negative electrode terminal lead 36 are fitted, so that positioning is facilitated and the connection by welding is strengthened, and the stability of the connection is improved. is doing. Therefore, this modification can provide a battery that is more stable in connection and that is suitable for large currents.

FIG. 14 shows a positive electrode portion of a battery 105 which is a modification of the battery 104 of the first embodiment. The negative electrode side is configured symmetrically with the positive electrode side and is not shown. In the battery 104, the electrode group side positive lead 12 is arranged between the positive electrode current collecting tab 7 a or the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7 a and the second positive electrode insulation reinforcing member 25. The difference is that the positive electrode current collecting tab 7a or the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7a and the first positive electrode insulation reinforcing member 24 are arranged with the electrode group side positive electrode lead 12. is there. The same applies to the negative electrode of the battery 105, and the electrode group side negative electrode lead 14 is disposed between the negative electrode current collecting tab 8 a or the backup negative electrode lead 13 sandwiching the negative electrode current collecting tab 8 a and the first negative electrode insulation reinforcing member 37. ing. Similar to the battery 104, the battery 105 is easily positioned by fitting and the connection by welding is further strengthened, and the connection stability is improved. Therefore, the battery 105 of this modification can provide a battery that is more stable in connection and is suitable for large currents.

FIG. 15A shows a positive electrode portion of a battery 106 which is a modified example of the battery 100 of the first embodiment. FIG. 15B shows a negative electrode portion of the battery 106. The negative electrode part of FIG. 15B is configured symmetrically with the positive electrode part of FIG. 15A. 15A and 15B, the first extension 23b of the positive terminal lead 23 extends to the side opposite to the electrode group 2 side, and the first extension 36b of the negative terminal lead 36 is an electrode. It extends to the side opposite to the group 2 side. The positive electrode current collecting tab 7a or the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7a, the electrode group side positive electrode lead 12 and the positive electrode terminal lead 23 are composed of the positive electrode current collecting tab 7a or the positive electrode current collecting tab 7a. The lead 11, the electrode group side positive lead 12, and the positive terminal lead 23 are arranged in this order. The negative electrode current collecting tab 8a or the backup negative electrode lead 13 sandwiching the negative electrode current collecting tab 8a, the electrode group side negative electrode lead 14 and the negative electrode terminal lead 36 are backed up by sandwiching the negative electrode current collecting tab 8a or the negative electrode current collecting tab 8a. The negative electrode lead 13, the electrode group side negative electrode lead 14, and the negative electrode terminal lead 36 are arranged in this order. The structure shown in FIGS. 15A and 15B is more compact in lead wiring than that shown in FIGS. 5 and 6. However, since the lead thickness can be increased, a battery suitable for a large current can be provided.

FIG. 16 shows a positive electrode portion of a battery 107 which is a modification of the battery 106 of the first embodiment. The negative electrode side is configured symmetrically with the positive electrode side and is not shown. In the battery 107, the positive electrode current collecting tab 7a or the backup positive electrode lead 11, the electrode group side positive electrode lead 12, and the positive electrode terminal lead 23 sandwiching the positive electrode current collecting tab 7a are the electrode group side positive electrode lead 12, the positive electrode current collecting tab 7a, or The backup positive electrode lead 11 and the positive electrode terminal lead 23 sandwiching the positive electrode current collecting tab 7a are arranged in this order. Similarly to the positive electrode side, in the battery 107, the negative electrode current collector tab 8a or the backup negative electrode lead 13 sandwiching the negative electrode current collector tab 8a, the electrode group side negative electrode lead 14, and the negative electrode terminal lead 36 are the electrode group side negative electrode lead. 14, the negative electrode current collecting tab 8 a or the backup negative electrode lead 13 and the negative electrode terminal lead 36 sandwiching the negative electrode current collecting tab 8 a are arranged in this order. The structure shown in FIG. 16 is similar to the structure shown in FIG. 15 in that the lead wiring is more compact than in FIGS. 5 and 6, but the lead thickness can be increased. Can provide.

FIG. 17 shows a positive electrode portion of a battery 108 which is a modification of the battery 106 of the first embodiment. The negative electrode side is configured symmetrically with the positive electrode side and is not shown. In the battery 106 of FIG. 15, the electrode group side positive lead 12 and the positive external terminal 17 are in direct contact. In the battery 107 of FIG. 16, the positive electrode current collecting tab 7 a or the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7 a is in contact with the positive electrode external terminal 17. On the other hand, in the battery 108 of FIG. 17, the positive electrode external terminal 17 is not in direct contact with any of the positive electrode current collecting tab 7a, the backup positive electrode lead 11 sandwiching the positive electrode current collecting tab 7a, and the current collector side positive electrode lead 12. The negative electrode side is the same as the positive electrode side. The structure shown in FIG. 17 is similar to the structure shown in FIG. 15 in that the lead wiring is more compact than in FIGS. 5 and 6, but the lead thickness can be increased. Can provide.

Even if the battery of the first embodiment described above is a thin battery, the thickness of the lead in the exterior member 1 can be increased, which is suitable for a large current.

In addition, although a terminal part may be applied to both a positive electrode terminal part and a negative electrode terminal part, it is also possible to apply to any one of a positive electrode terminal part or a negative electrode terminal part.

(Second Embodiment)
The battery pack of the second embodiment includes one or more batteries of the first embodiment. Examples of the assembled battery of the battery according to the first embodiment are shown in FIGS.

As shown in FIG. 18, the battery pack 200 uses the batteries 100 to 108 of the first embodiment as unit cells. The battery pack 200 may be covered with a laminate (not shown). Between the top surface of the negative electrode external terminal 32 of the first unit cell 60 and the top surface of the negative electrode external terminal 32 of the second unit cell 61, a triangular columnar conductive connecting member 62 is disposed. Further, a triangular prism-shaped conductive connecting member 62 is disposed between the top surface of the positive electrode external terminal 17 of the first unit cell 60 and the top surface of the positive electrode external terminal 17 of the second unit cell 61. The two top surfaces and the conductive connecting member 62 are electrically connected to each other by welding. For welding, for example, laser welding, arc welding, or resistance welding is used. As a result, an assembled battery unit 63 in which the first unit cell 60 and the second unit cell 61 are connected in parallel is obtained. A battery pack is obtained by connecting the assembled battery units 63 in series by the bus bar 64.

A battery pack 201 shown in FIG. 19 uses the battery 100 of the first embodiment as a unit cell. The first unit cell 60 and the second unit cell 61 connected in series using the conductive connecting member 62 are used as the assembled battery unit 65, and the assembled battery units 65 are connected in series by the bus bar 64. Make up the battery pack. The method of electrically connecting the first unit cell 60 and the second unit cell 61 using the conductive connecting member 62 is the same as described with reference to FIG.

18 and FIG. 19, the adjacent first unit cell 60 and second unit cell 61 are stacked with the main surfaces of the exterior members 1 facing each other. For example, in the assembled battery unit 63 shown in FIG. 18, the main surface of the first exterior portion 5 of the first unit cell 60 faces the main surface of the first exterior portion 5 of the second unit cell 61. ing. Further, in the adjacent assembled battery unit 63, the main surface of the second exterior portion 6 of the second unit cell 61 of one assembled battery unit 63 and the second unit cell of the other assembled battery unit 63. The main surface of the 61st 2nd exterior part 6 faces. Thus, the volume energy density of an assembled battery can be made high by laminating | stacking a battery by making the main surfaces of an exterior member face each other.

Further, as shown in FIGS. 18 and 19, it is preferable that there is an insulating space between the unit cell 60 and the unit cell 61, or between the

unit cells

60 and 60 and the

unit cells

61 and 61, and 0.03 mm or more. Or an insulating member (for example, resin such as polypropylene, polyphenylene sulfide, epoxy, fine ceramic such as alumina or zirconia) or the like can be sandwiched therebetween.

Since the positive electrode external terminal 17 and the negative electrode external terminal 32 have a truncated pyramid-shaped head, a unit is provided at one of the two heads (for example, the first and second inclined surfaces) (first inclined surface). A bus bar can be connected to the external terminal of the cell and the other (second inclined surface). That is, two directions can be connected with one head. As a result, the path for electrically connecting the batteries can be shortened, so that it is easy to flow a large current through the battery pack with low resistance.

Since the battery pack of the second embodiment includes at least one battery of the first embodiment, the battery pack can be thinned and improved in flexibility, excellent in reliability, and capable of reducing manufacturing costs. Can be provided.
The battery pack is used as a power source for electronic devices and vehicles (railway vehicles, automobiles, motorbikes, light vehicles, trolley buses, etc.), for example.
As described above, the assembled battery may include a plurality of batteries electrically connected in series, parallel, or a combination of series and parallel. In addition to the assembled battery, the battery pack can include a circuit such as a battery control unit (BMU), but the battery control unit includes a circuit (for example, a vehicle) on which the assembled battery is mounted. Can be used as The battery control unit has a function of preventing overcharge and overdischarge by monitoring the voltage and / or current of the cell and the assembled battery.

(Third embodiment)
The third embodiment relates to a power storage device. The battery packs 200 and 201 of the second embodiment can be mounted on the power storage device 300. A power storage device 300 illustrated in the conceptual diagram of FIG. 20 includes battery packs 200 and 201, an inverter 302, and a converter 301. External AC power supply 303 is converted into DC by converter 301, battery packs 200 and 201 are charged, AC conversion is performed by inverter 302 of the DC power supply from battery packs 200 and 201, and electricity is supplied to load 304 connected to power storage device 300. It is the composition to do. By setting it as the electrical storage apparatus 300 of this structure which has the battery packs 200 and 201 of embodiment, the electrical storage apparatus excellent in the battery characteristic is provided. Instead of the battery packs 200 and 201, the batteries 100 to 104 can be used.

(Fourth embodiment)
The fourth embodiment relates to a vehicle. The vehicle of the fourth embodiment uses the battery packs 200 and 201 of the second embodiment. The configuration of the vehicle according to the present embodiment will be briefly described with reference to the schematic diagram of the vehicle 400 in FIG. The vehicle 400 includes battery packs 200 and 201, a vehicle body 401, a motor 402, wheels 403, and a control unit 404. The battery packs 200 and 201, the motor 402, the wheels 403, and the control unit 404 are disposed on the vehicle body 401. The control unit 404 converts the power output from the battery packs 200 and 201 and adjusts the output. The motor 402 rotates the wheel 403 using the electric power output from the battery packs 200 and 201. Note that the vehicle 400 includes an electric vehicle such as a train and a hybrid vehicle having another drive source such as an engine. The battery packs 200 and 201 may be charged by regenerative energy from the motor 402. What is driven by the electric energy from the battery packs 200 and 201 is not limited to a motor, and may be used as a power source for operating an electric device included in the vehicle 400. It is preferable to obtain regenerative energy when the vehicle 400 is decelerated and to charge the battery packs 200 and 201 using the obtained regenerative energy. By using the vehicle 400 having this configuration having the battery packs 200 and 201 of the embodiment, a vehicle having excellent battery characteristics is provided. Instead of the battery packs 200 and 201, the batteries 100 to 104 can be used.

(Fifth embodiment)
The fifth embodiment relates to a flying object (for example, a multicopter). The flying body of the fifth embodiment uses the battery packs 200 and 201 of the second embodiment. The configuration of the flying object according to this embodiment will be briefly described with reference to the schematic diagram of the flying object (quad copter) 500 in FIG. The flying object 500 includes battery packs 200 and 201, an aircraft skeleton 501, a motor 502, a rotary blade 503, and a control unit 504. The battery packs 200 and 201, the motor 502, the rotary blade 503, and the control unit 504 are arranged in the body frame 501. The control unit 504 converts the power output from the battery packs 200 and 201 and adjusts the output. The motor 502 rotates the rotary blade 503 using the electric power output from the battery packs 200 and 201. By using the flying object 500 of this configuration having the battery packs 200 and 201 of the embodiment, a flying object having excellent battery characteristics is provided. Instead of the battery packs 200 and 201, the batteries 100 to 104 can be used.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Exterior member, 2 ... Electrode group, 3 ... Positive electrode terminal part, 4 ... Negative electrode terminal part, 5 ... 1st exterior part, 5a ... Opening part, 5b ... Flange part, 5c ... Bottom face, 5d ... Inclined surface, 6 DESCRIPTION OF SYMBOLS 2nd exterior part, 7 ... Positive electrode, 7a ... Positive electrode current collection tab, 8 ... Negative electrode, 8a ... Negative electrode current collection tab, 12 ... Electrode group side positive electrode lead, 14 ... Electrode group side negative electrode lead, 15, 30 ... First 1 through-hole of exterior part, 16, 31 ... burring part, 17 ... positive electrode external terminal, 18a ... positive electrode insulation member, 18b ... positive electrode reinforcement member, 19, 34 ... insulation gasket, 20 ... positive electrode terminal insulation member, 21 ... head , 23 ... positive electrode terminal lead, 24 ... first positive electrode insulation reinforcing member, 25 ... second positive electrode insulation reinforcing member, 32 ... negative electrode external terminal, 33a ... negative electrode insulating member, 33b ... negative electrode reinforcement member, 35 ... negative electrode terminal Insulating member, 36 ... negative electrode terminal lead, 37 ... first negative electrode insulation Strong member, 38 ... second insulation reinforcing member, 39 ... guide hole, 40, 41, 43 ... welded portion, 42 ... cut-off portion, 60 ... first unit cell, 61 ... second unit cell, 62 ... conductive 63, 65 ... unit of assembled battery, 64 ... bus bar 100-108 ... battery, 200, 201 ... battery pack, 300 ... power storage device, 301 ... converter, 302 ... inverter, 303 ... external AC power source, 304 ... Load 400, vehicle 401, vehicle body 402, motor, 403 wheel, 404 control unit, 500 flying object, 501 body frame, 502 motor, 503 rotor, 504 control unit

Claims

A positive electrode current collecting tab electrically connected to the positive electrode; a negative electrode; and a negative electrode current collecting tab electrically connected to the negative electrode. A flat electrode group in which the negative electrode current collecting tab, which is positioned on one end surface and wound in a flat shape, is positioned on the second end surface;
An electrode group side positive lead electrically connected to the positive current collecting tab;
An electrode group side negative electrode lead electrically connected to the negative electrode current collecting tab;
In a space formed by welding the flange portion of the first exterior portion and the second exterior portion, including a first exterior portion having a flange portion at the opening and a second exterior portion. An exterior member containing the electrode group;
The first exterior part has a through hole on the positive electrode current collecting tab side, includes a positive electrode external terminal including a head part and a shaft part extending from the head part, and a positive electrode terminal lead having a through hole, A positive electrode having a head protruding outside the first exterior part, the shaft part being inserted into a through hole of the positive terminal lead, and the shaft part being caulked and fixed to the first exterior part and the positive terminal lead A terminal section;
The first exterior part has a through hole on the negative electrode current collecting tab side, includes a negative electrode external terminal including a head part and a shaft part extending from the head part, and a negative electrode terminal lead having a through hole, A negative electrode in which a head protrudes outside the first exterior part, the shaft part is inserted into a through hole of the negative electrode terminal lead, and the shaft part is caulked and fixed to the first exterior part and the negative electrode terminal lead. A terminal section;
Including
The positive terminal lead has a first extension part extending to the second exterior part side,
On the side opposite to the electrode group side of the electrode group side positive lead, the first extended portion of the electrode group side positive lead,
The first extension of the positive terminal lead and the first extension of the electrode group side positive lead are welded,
The first extension part of the welded positive electrode terminal lead and the tip of the first extension part of the electrode group side positive electrode lead are formed on the second exterior part parallel to the opening of the first exterior part. Perpendicular or nearly perpendicular to the surface,
The negative electrode terminal lead has a first extension part extending to the second exterior part side,
On the opposite side of the electrode group side negative electrode lead to the electrode group side, the first extended part of the electrode group side negative electrode lead,
The first extension of the negative terminal lead and the first extension of the electrode group side negative lead are welded,
The first extended portion of the welded negative electrode terminal lead and the tip of the first extended portion of the electrode group side negative electrode lead are formed on the second exterior portion parallel to the opening of the first exterior portion. A battery that is perpendicular or nearly perpendicular to a surface.
The electrode group is one or more,
The thickness of the battery is 5 mm or more and 30 mm or less,
The thickness of the electrode group side positive electrode lead and the electrode group side negative electrode lead is 0.5 mm or more and 3.0 mm or less,
The battery according to claim 1, wherein a thickness of the positive terminal lead and the negative terminal lead is 0.5 mm or more and 3.0 mm or less.
A first exterior part of the welded positive electrode terminal lead and a tip of the first extension part of the electrode group side positive electrode lead are parallel to the opening of the first exterior part. 80 ° or more and 100 ° or less with respect to the surface of
A first exterior portion of the welded negative electrode terminal lead and a distal end of the first extension portion of the electrode group side negative electrode lead are parallel to the opening of the first exterior portion. The battery according to claim 1, wherein the angle is 80 ° or more and 100 ° or less with respect to the surface.
The first extension part of the positive terminal lead extends to the electrode group side,
4. The battery according to claim 1, wherein the first extending portion of the negative electrode terminal lead extends to the electrode group side. 5.
The positive terminal lead has a second extension part,
The positive current collecting tab is sandwiched between the second extension portion of the positive terminal lead and the positive electrode lead on the electrode group side,
The second extension portion of the positive terminal lead supports the side of the positive current collecting tab opposite to the side where the electrode group side positive lead exists,
The negative terminal lead has a second extension part,
The negative electrode current collection tab is sandwiched between the second extension portion of the negative electrode terminal lead and the electrode group side negative electrode lead,
5. The battery according to claim 1, wherein the second extension portion of the negative electrode terminal lead supports a side of the negative electrode current collecting tab opposite to a side where the electrode group side negative electrode lead exists. .
The positive terminal lead has a second extension part,
Sandwiching the electrode group side positive lead between the positive current collecting tab and the second extension of the positive terminal lead;
The negative terminal lead has a second extension part,
The battery according to any one of claims 1 to 4, wherein the electrode group-side negative electrode lead is sandwiched between the negative electrode current collecting tab and a second extending portion of the negative electrode terminal lead.
The first extension part of the positive electrode terminal lead extends to the side opposite to the electrode group side,
4. The battery according to claim 1, wherein the first extension portion of the negative electrode terminal lead extends to a side opposite to the electrode group side. 5.
The positive current collecting tab, the electrode group side positive lead and the positive terminal lead are arranged in the order of the positive current collecting tab, the electrode group side positive lead, the positive terminal lead,
The battery according to claim 7, wherein the negative electrode current collecting tab, the electrode group side negative electrode lead, and the negative electrode terminal lead are arranged in the order of the negative electrode current collecting tab, the electrode group side negative electrode lead, and the negative electrode terminal lead.
The positive electrode current collecting tab, the electrode group side positive electrode lead and the positive electrode terminal lead are arranged in the order of the electrode group side positive electrode lead, the positive electrode current collecting tab and the positive electrode terminal lead,
The battery according to claim 7, wherein the negative electrode current collecting tab, the electrode group side negative electrode lead, and the negative electrode terminal lead are arranged in the order of the electrode group side negative electrode lead, the negative electrode current collecting tab, and the negative electrode terminal lead.
The first extension part of the positive electrode terminal lead and the first extension part of the electrode group side positive electrode lead are fitted,
The battery according to claim 1, wherein the first extension part of the negative electrode terminal lead and the first extension part of the electrode group side negative electrode lead are fitted.
A battery pack including one or more batteries according to claim 1.
A power storage device comprising the battery according to claim 1 or the battery pack according to claim 9.
A vehicle including the battery according to claim 1 or the battery pack according to claim 9.
A flying object including the battery according to claim 1 or the battery pack according to claim 9.