WO2019182117A1

WO2019182117A1 - Busbar, battery pack, and electrical device

Info

Publication number: WO2019182117A1
Application number: PCT/JP2019/012110
Authority: WO
Inventors: 宏和飯塚; 鈴木　潤
Original assignee: 藤森工業株式会社
Priority date: 2018-03-23
Filing date: 2019-03-22
Publication date: 2019-09-26
Also published as: JPWO2019182117A1; JP7389019B2

Abstract

This busbar is electrically connected to a battery having a first electrode terminal and a second electrode terminal. The busbar has a structure in which a first resin layer, a first conductive layer, a second resin layer, a second conductive layer, and a third resin layer are stacked in this order. A part of the first conductive layer is exposed as a first part that can be electrically connected to the first electrode terminal. A part of the second conductive layer is exposed as a second energized part that can be electrically connected to the second electrode terminal.

Description

Busbar, battery pack, and electric device

The present invention relates to a bus bar, an assembled battery, and an electric device.
This application claims priority based on Japanese Patent Application No. 2018-056556 for which it applied to Japan on March 23, 2018, and uses the content here.

As environmental awareness increases, secondary batteries such as lithium ion batteries are attracting attention as storage batteries for storing electrical energy (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2000-357494

In storage batteries for electric vehicles and the like, assembled batteries configured by connecting a plurality of single cells (lithium ion batteries or the like) are used to increase the capacity. The plurality of single cells are connected in parallel or in series via a bus bar made of metal or the like, for example. It is desired that the bus bar can be easily connected to the unit cell.

An object of one embodiment of the present invention is to provide a bus bar, an assembled battery, and an electric device that can easily connect a plurality of single cells constituting the assembled battery.

A first aspect of the present invention is a bus bar that is electrically connected to a battery having a first electrode terminal and a second electrode terminal. The bus bar has a structure in which a first insulating layer, a first conductive layer, a second insulating layer, a second conductive layer, and a third insulating layer are stacked in this order. A part of the first conductive layer is exposed as a first current-carrying portion that can be electrically connected to the first electrode terminal. A part of the second conductive layer is exposed as a second current-carrying portion that can be electrically connected to the second electrode terminal.

According to a second aspect of the present invention, in the bus bar of the first aspect, a first notch that exposes the first current-carrying portion is formed in the first insulating layer. In the bus bar, a second notch for exposing the second current-carrying portion is formed in the first insulating layer, the first conductive layer, and the second insulating layer.

According to a third aspect of the present invention, in the bus bar of the first aspect, a first notch that exposes the first current-carrying portion is formed in the first insulating layer. The bus bar has a second notch that exposes the second current-carrying portion in the third insulating layer.

A fourth aspect of the present invention is an assembled battery including the bus bar according to any one of the first to third aspects and a plurality of the batteries. At least one of the first electrode terminals is electrically connected to the first energization unit. At least one of the second electrode terminals is electrically connected to the second energization unit.

The fifth aspect of the present invention has the following configuration. In the assembled battery of the fourth aspect, the battery has a flat shape.

The sixth aspect of the present invention has the following configuration. In the assembled battery according to the fourth or fifth aspect, the battery includes a battery body and a housing body having an internal space for housing the battery body. The said container is comprised from the laminated body by which the metal layer and the resin layer were laminated | stacked. The resin layer is directed toward the internal space.

According to a seventh aspect of the present invention, the assembled battery according to any one of the fourth to sixth aspects further includes a battery outer package that covers the battery. The battery exterior body includes at least a pair of facing exterior plates. The exterior plates abut on each other at a plurality of abutting portions at intervals in the width direction. Each of the batteries is accommodated in a plurality of cylindrical portions defined by the contact portions.

The eighth aspect of the present invention is the assembled battery of the seventh aspect, further comprising a thermal diffusion sheet that contacts two or more of the plurality of batteries via the battery outer package. The thermal diffusion sheet has a thermal conductivity higher than the thermal conductivity at the contacted surface of the battery exterior body.

A ninth aspect of the present invention is an electric device including the assembled battery according to any one of the fourth to eighth aspects and a drive mechanism that is driven by the assembled battery.

Another aspect of the present invention is a bus bar that is electrically connected to a battery having a first electrode terminal and a second electrode terminal. The bus bar has a structure in which a first resin layer, a first conductive layer, a second resin layer, a second conductive layer, and a third resin layer are laminated in this order. A first notch is formed in the first resin layer to expose a first current-carrying portion that is a part of the first conductive layer and can be electrically connected to the first electrode terminal. Yes. The second resin layer, the first conductive layer, and the second resin layer are part of the second conductive layer and can be electrically connected to the second electrode terminal. A second notch that exposes the current-carrying portion is formed.

According to one embodiment of the present invention, it is possible to easily connect a plurality of single cells constituting an assembled battery.

It is a disassembled perspective view which shows the assembled battery using the bus bar of 1st Embodiment. It is a perspective view after the assembly of the assembled battery shown in FIG. It is a perspective view which shows the example of the cell used for the assembled battery shown in FIG. It is a perspective view of a bus bar and a single cell shown in FIG. It is a disassembled perspective view of the bus bar shown in FIG. It is a block diagram of the other example of the assembled battery using the bus bar shown in FIG. It is a schematic diagram which decomposes | disassembles and shows a part of assembled battery shown in FIG. It is a schematic diagram which expands and shows a part of assembled battery shown in FIG. It is a schematic diagram of the assembled battery shown in FIG. It is a block diagram of the further another example of the assembled battery using the bus bar shown in FIG. It is a disassembled perspective view which shows the example of the connection structure of the lead | read | reed and bus bar of a cell. It is a top view which decomposes | disassembles and shows the connection structure of FIG. It is a figure showing typically the electric device of one embodiment. It is a perspective view of the modification of the assembled battery shown in FIG. It is a disassembled perspective view of the bus bar of 2nd Embodiment.

FIG. 1 is an exploded perspective view showing an assembled battery 10 using the bus bar 3 of the embodiment. FIG. 2 is a perspective view of the assembled battery 10 after assembly. FIG. 3 is a perspective view showing an example of the unit cell 1 used in the assembled battery 10.
As shown in FIGS. 1 and 2, the assembled battery 10 includes a plurality of single cells 1 (batteries), a battery outer package 2, and a bus bar 3.

The assembled battery 10 includes one or a plurality of battery exterior bodies 2. The assembled battery 10 shown in FIG. 1 includes one battery outer body 2. The battery exterior body 2 includes a pair of

exterior plates

6 and 6 facing each other. The

exterior plates

6 and 6 are referred to as a first exterior plate 6A and a second exterior plate 6B in order from the top in FIG.

The exterior plate 6 is made of, for example, a metal or a non-metallic material (for example, resin). The metal constituting the exterior plate 6 may be, for example, copper, nickel, iron, stainless steel, aluminum, or an alloy including one or more of these. Non-metallic materials constituting the exterior plate 6 include polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); polyolefin resins such as polypropylene; polyamide resins such as nylon (Ny) Polyimide resin; fluorine resin; acrylic resin; polyurethane resin and the like.

The exterior plate 6 may have a single layer structure or a multilayer structure. The exterior plate 6 may be a multilayer structure including a metal layer and a non-metal layer. The exterior plate 6 is formed in a rectangular shape, for example, a rectangular shape in plan view.

1 and 2, the X direction is the width direction of the exterior plate 6. The Y direction is an extending direction orthogonal to the X direction in a plane along the exterior plate 6 (for example, the substrate portion 11). The Z direction is a direction orthogonal to the X direction and the Y direction, and is the thickness direction of the exterior plate 6. Plan view means viewing from the Z direction.

The facing

exterior plates

6 and 6 are in contact with each other at a plurality of contact portions 7. The contact portion 7 is formed in a band shape having a constant width along the Y direction, for example. The plurality of contact portions 7 are formed at intervals in the X direction. A portion of the exterior plate 6 between the

contact portions

7 and 7 adjacent to each other in the X direction is referred to as an intermediate portion 8 (non-contact portion). The intermediate portion 8 includes a substrate portion 11 and a pair of

side plate portions

12 and 12 that are inclined with respect to the substrate portion 11.

The substrate unit 11 is formed along the XY plane, for example. The inner surface of the substrate portion 11 of the first exterior plate 6A is in surface contact with one surface of the unit cell 1. The inner surface of the substrate portion 11 of the second exterior plate 6B is in surface contact with the other surface of the unit cell 1.

The

side plate portions

12 and 12 extend from both side edges of the substrate portion 11 toward the

contact portions

7 and 7, respectively. The

side plate portions

12 and 12 are inclined and extended so as to approach the mating exterior plate 6 while being widened from both side edges of the substrate portion 11. The

side plate portions

12 and 12 have a flat shape and are inclined with respect to the substrate portion 11 at an angle θ1 (0 ° <θ1 <90 °) (see FIG. 1).
The intermediate portion 8 has a bent shape that protrudes in a direction (outward) away from the counterpart exterior plate 6 with respect to the XY plane passing through the

contact portions

7 and 7.

As shown in FIG. 2, the

intermediate portions

8 and 8 of the facing

exterior plates

6 and 6 form a hollow rectangular tubular portion 14. The internal space of the cylindrical portion 14 is a battery housing portion 15. The cylindrical portion 14 is partitioned by the

contact portions

7 and 7. The

exterior plates

6 and 6 have two or more cylindrical portions 14 arranged in the width direction (X direction). The number of cylindrical portions formed by the pair of facing exterior plates is preferably 2 or more, and can be, for example, 2 to 200.

In the assembled battery 10 shown in FIG. 2, the

exterior plates

6 and 6 constituting the battery exterior body 2 are in contact with each other at four contact portions 7 at intervals in the X direction. Therefore, the battery outer package 2 has three cylindrical portions 14. The

exterior plates

6 and 6 are all formed continuously over the three cylindrical portions 14.

In the battery pack 10 shown in FIG. 2, since the

side plate portions

12 and 12 are inclined, the cylindrical portion 14 has a hexagonal cylindrical shape including the substrate portion 11 and the side plate portion 12. One intermediate portion has a substrate portion and a pair of side plate portions that are inclined so as to approach the counterpart plate while being widened, and the other intermediate portion is the substrate portion and the opposite plate while being widened. When it has a pair of side plate part inclined so that it may approach a body, the shape of the cylindrical part comprised from these board | substrate parts and a side plate part is a hexagonal cylinder shape. It is preferable that the cylindrical portion is a hexagonal cylindrical shape because the strength of the battery outer body is improved.

The

contact portions

7 and 7 can also be bonded to each other by an adhesive layer 9 (see FIG. 1) made of an adhesive. Examples of adhesives for bonding the

contact portions

7 and 7 include polyolefin adhesives, urethane adhesives, epoxy adhesives, acrylic adhesives, urethane adhesives, nylon adhesives, and polyester adhesives. An agent etc. can be mentioned. The adhesive may be an insulating material.

In the battery exterior body 2 shown in FIG. 2, since the plurality of cylindrical portions 14 are arranged side by side in the width direction (X direction) of the exterior plate 6, the honeycomb in which the plurality of cylindrical portions 14 are regularly arranged It is a structure. The number of battery outer bodies 2 (a pair of outer plates 6 and 6) may be one or two or more (for example, 2 to 20). When there are a plurality of battery exterior bodies 2, the plurality of battery exterior bodies 2 can be stacked in the thickness direction (Z direction).

As shown in FIG. 3, the cell 1 is, for example, a lithium ion battery. The unit cell 1 includes a battery body 50 and a container 51. The container 51 includes a tray-shaped container main body 52 and a lid 53 that closes the opening of the container main body 52. The housing 51 has an internal space for housing the battery main body 50. The container 51 is formed by overlapping the container body 52 and the lid 53 and heat-sealing the peripheral edge 54. Reference numeral 55 denotes a positive electrode lead (first electrode terminal) connected to the electrode (positive electrode) of the battery body 50. Reference numeral 56 denotes a negative electrode lead (second electrode terminal) connected to the electrode (negative electrode) of the battery body 50. The positive electrode lead 55 and the negative electrode lead 56 extend from one end of the container 51.

The battery body 50 includes, for example, a positive electrode plate (not shown), a positive electrode active material layer (not shown) in contact with the positive electrode plate, a negative electrode plate (not shown), and a negative electrode active material layer (not shown) in contact with the negative electrode plate. And a separator (not shown) that separates the positive electrode active material layer and the negative electrode active material layer, and an electrolyte (not shown). The positive electrode plate and the negative electrode plate are made of metal, for example. The positive electrode active material layer includes, for example, a positive electrode active material such as a lithium-based material. The negative electrode active material layer includes a negative electrode active material such as a carbon-based material. The battery body 50 is preferably flat and has a constant thickness.

The container main body 52 and the lid part 53 that constitute the container 51 may be constituted by, for example, a laminate including a metal layer 57 and a resin layer 58 laminated on the metal layer 57. The metal layer 57 is made of a metal such as aluminum or stainless steel. The resin layer 58 is made of a resin such as polyethylene or polypropylene. The container 51 is configured with the resin layer 58 facing the internal space.
Although not shown, the laminate is formed on the metal layer, the first resin layer laminated on the first surface of the metal layer, and the second surface of the metal layer (the surface opposite to the first surface). A structure including a laminated second resin layer (that is, a resin layer / metal layer / resin layer structure) may be used. This structure is preferable from the viewpoint of processability and durability of the laminate.

The single cell 1 has a flat shape and is accommodated in the battery accommodating portion 15 (see FIG. 2) of the battery outer package 2 with the thickness direction in the Z direction. The unit cell 1 having a flat shape means that the thickness dimension (Z direction dimension) of the unit cell 1 is smaller than the width direction (X direction) dimension and the extending direction (Y direction) dimension. . Since the unit cell 1 has a flat shape, the assembled battery 10 can be thinned.

As shown in FIG. 2, the single cells 1 are respectively accommodated in a plurality (three in FIG. 2) of cylindrical portions 14. Since the unit cell 1 is accommodated in the cylindrical portion 14, the unit cell 1 is externally mounted on the battery exterior body 2. It is preferable that the unit cell 1 is accommodated in the cylindrical part 14 so that insertion / extraction is possible.

FIG. 4 is a perspective view of the bus bar 3 and the cell 1. FIG. 5 is an exploded perspective view of the bus bar 3. As shown in FIG. 5, the bus bar 3 includes a first resin layer 31, a first conductive layer 32, a second resin layer 33, a second conductive layer 34, and a third resin layer 35 in this order. It has a laminated structure. First resin layer 31 (first insulating layer), first conductive layer 32, second resin layer 33 (second insulating layer), second conductive layer 34, and third resin layer 35 ( The third insulating layer is laminated in the length direction.

The bus bar 3 is a sheet-like laminate including three

resin layers

31, 33 and 35 and two

conductive layers

32 and 34. The bus bar is configured by laminating a plurality of resin layers and one or a plurality of conductive layers. The bus bar is a laminate including a resin layer and a conductive layer, and the resin layer is disposed on the outermost surface side. For example, the resin layers and the conductive layers are alternately stacked. Since the bus bar is a sheet-like laminate, there is an advantage that it is easy to process when an assembled battery is manufactured.

The first conductive layer 32 is laminated on the first surface 31 a of the first resin layer 31. The second resin layer 33 is laminated on the first surface 32a of the first conductive layer 32 (the surface opposite to the surface on the first resin layer 31 side). The second conductive layer 34 is laminated on the first surface 33a of the second resin layer 33 (the surface opposite to the surface on the first conductive layer 32 side). The third resin layer 35 is laminated on the first surface 34a of the second conductive layer 34 (the surface opposite to the surface on the second resin layer 33 side).

As shown in FIG. 4, the bus bar 3 is formed in a strip shape. In FIG. 4, the bus bar 3 extends in the X direction. The width direction of the bus bar 3 coincides with the Y direction. The bus bar 3 is parallel to the XY plane. The resin layers 31, 33, 35 and the

conductive layers

32, 34 can also be formed in a strip shape having the same width.

The resin layers 31, 33, and 35 can be wider than the

conductive layers

32 and 34. Making the widths of the resin layers 31, 33, 35 wider than the widths of the

conductive layers

32, 34 is preferable from the viewpoint of preventing a short circuit between the

conductive layers

32, 34. The width of the conductive layer can be 3 to 50 mm, for example, and can be 5 to 20 mm. When the conductive layer has a certain width (for example, 3 mm or more), there is an advantage that current collection is facilitated.

The bus bar 3 shown in FIG. 4 and FIG. 5 is a bus bar for an assembled battery that can easily connect a plurality of single cells constituting the assembled battery. In addition to the assembled battery, an electronic circuit, an electronic device, and an electric device It can be used as a member. When the bus bar is used as a member of an electronic circuit, an electronic device, or an electric device, the bus bar is strip-like and thin, and has an effect that it can be easily connected to a terminal.

As shown in FIG. 5, the first conductive layer 32 and the second conductive layer 34 are made of, for example, metal. Examples of the metal constituting the

conductive layers

32 and 34 include copper, aluminum, stainless steel, nickel, and iron. The metal constituting the

conductive layers

32 and 34 may be an alloy including two or more of these. The

conductive layers

32 and 34 are metal foils containing, for example, one or more of copper, aluminum, stainless steel, nickel, and iron. The

conductive layers

32 and 34 may have a structure having a base metal layer and a plating layer formed on the surface thereof. A base metal layer and a plating layer are comprised, for example from the above-mentioned metal. For example, the

conductive layers

32 and 34 may have a structure including a base metal layer made of copper and a nickel plating layer. The thickness of the

conductive layers

32 and 34 is not particularly limited, but can be, for example, about 20 to 500 μm, or about 50 to 400 μm. In addition, as a constituent material of the 1st conductive layer 32 and the 2nd conductive layer 34, although not only a metal but a carbon material, a conductive resin, etc. can be considered, a metal is preferable at a conductive point.

The first resin layer 31, the second resin layer 33, and the third resin layer 35 are made of, for example, a resin film. Examples of the resin constituting the resin layers 31, 33, and 35 include polyolefin (polyethylene, polypropylene, etc.), polyester, polyamide, polyimide, polyurethane, fluororesin, acrylic resin, and the like. Examples of polyester include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT). Among these, a resin film having heat fusion properties is preferable, and polyolefin (polyethylene, polypropylene, etc.) is preferable.

Resin layers 31, 33, and 35 are insulating layers having insulating properties. The resin film may be an unstretched film, or a uniaxially stretched or biaxially stretched film. The thickness of the resin layers 31, 33, and 35 is not particularly limited, but can be, for example, about 10 to 500 μm, and can be about 100 to 300 μm. The material and film thickness of the resin layers 31, 33, and 35 may be different in each layer. The material and thickness of each layer can also be selected individually.

As shown in FIGS. 4 and 5, the first resin layer 31 has one or more first notches 36 formed therein. The first notch 36 can be rectangular when viewed from the thickness direction (Z direction) of the bus bar 3. In this embodiment, a plurality of first notches 36 are formed in the first resin layer 31. The plurality of first notches 36 are formed at intervals in the length direction of the bus bar 3.

The first notch 36 may have a shape other than a rectangle, for example, a semicircular shape, but is preferably rectangular from the viewpoint of connection with a lead. As shown in FIG. 5, the first notch 36 is formed at a position including the first side edge 31 b of the first resin layer 31. The first notch 36 is formed in a concave shape starting from the first side edge 31b toward the second side edge 31c. For example, the first cutout 36 is formed by two opposing

edges

36a and 36a extending in the Y direction from the first side edge 31b toward the second side edge 31c, and a back edge 36b along the X direction. This is a rectangular cutout. As shown in FIG. 4, the width of the first notch 36 (the dimension in the X direction) is the same as the width of the first lead (for example, the positive electrode lead 55) connected to the first current-carrying part 41, Greater than this width.

A part of the first conductive layer 32 is exposed by forming the first notch 36 in the first resin layer 31. This exposed portion is referred to as a first energization unit 41. The first energization part 41 is a partial region of the second surface 32 b (the surface opposite to the first surface 32 a) of the first conductive layer 32. Of the

leads

55 and 56 of the unit cell 1, the tip of the first lead (for example, the positive electrode lead 55) is in contact with the first energization unit 41. It is preferable that the front end portion of the first lead is overlapped with the first energization portion 41 and is in surface contact. When the first lead comes into contact with the first energization portion 41, the first conductive layer 32 and the first lead are electrically connected.

As shown in FIG. 5, one or a plurality of second notches 37 are formed in the first resin layer 31, the first conductive layer 32, and the second resin layer 33. The second notch 37 is formed by a notch 31 d of the first resin layer 31, a notch 32 b of the first conductive layer 32, and a notch 33 b of the second resin layer 33. The

notches

31d, 32b, and 33b have the same shape when viewed from the thickness direction (Z direction) of the bus bar 3, and are in positions that overlap each other. The second notch 37 is a general term for the

notches

31d, 32b, and 33b. In this embodiment, a plurality of second notches 37 are formed in the first resin layer 31, the first conductive layer 32, and the second resin layer 33. The plurality of second notches 37 are formed at intervals in the length direction of the bus bar 3.

The second notch 37 can be rectangular when viewed from the thickness direction (Z direction) of the bus bar 3. The second notch 37 may have a shape other than a rectangle, for example, a semicircular shape, but is preferably rectangular from the viewpoint of connection with a lead. The second notch 37 is formed at a position including the resin layers 31 and 33 and the first side edge of the conductive layer 32. The second notch 37 is formed in a concave shape from the first side edge as a starting point toward the second side edge. For example, the notch 31d of the first resin layer 31 includes two opposing edges 31d1 and 31d1 extending in the Y direction from the first side edge 31b toward the second side edge 31c, and a back edge 31d2 along the X direction. Is a rectangular cutout formed by The notch 32b and the notch 33b have the same rectangular shape as the notch 31d. The width (dimension in the X direction) of the second notch 37 is the same as or larger than the width of the second lead (for example, the negative electrode lead 56 shown in FIG. 4) connected to the second current-carrying portion 42. large.

A part of the second conductive layer 34 is exposed by forming the second notch 37 in the resin layers 31 and 33 and the conductive layer 32. As shown in FIG. 4, this exposed portion is referred to as a second energization unit 42. The second energization portion 42 is a partial region of the second surface 34 b (the surface opposite to the first surface 34 a) of the second conductive layer 34. Of the

leads

55 and 56 of the unit cell 1, the tip of the second lead (for example, the negative electrode lead 56) is in contact with the second energization unit 42. It is preferable that the tip of the second lead is overlapped with the second energization part 42 to make a surface contact. The second conductive layer 34 and the second lead are electrically connected when the second lead comes into contact with the second energization portion 42.

The first notch 36 and the second notch 37 are different from each other in the position in the length direction of the bus bar 3. As shown in FIG. 1, the bus bar 3 is formed with a plurality of notch groups 40 each having one first notch 36 and one second notch 37. The first notch 36 and the second notch 37 constituting the notch group 40 are formed at intervals in the length direction of the bus bar 3. The arrangement order of the first notch 36 and the second notch 37 is preferably common to the plurality of notch groups 40. In FIG. 1, three first notches 36 and three second notches 37 are alternately formed in the length direction of the bus bar 3.

As shown in FIG. 2, the bus bar 3 is preferably fixed by being sandwiched between the

contact portions

7 and 7 of the

exterior plates

6 and 6. In addition, as shown in FIG. 2, the bus bar 3 or the

leads

55 and 56 can be arranged in a planar shape without being bent. It can also be stacked on the plate 6.

As shown in FIGS. 1 and 2, the first leads (for example, positive electrode leads 55) of the plurality of single cells 1 are connected to the first conductive layer 32. Second leads (for example, negative electrode leads 56) of the plurality of unit cells 1 are connected to the second conductive layer 34. Therefore, the plurality of single cells 1 are connected in parallel by the bus bar 3.

FIG. 6 is a configuration diagram of an assembled battery 110 which is another example of the assembled battery using the bus bar 3. FIG. 7 is an exploded view showing a part of the battery pack 110 (part indicated by I in FIG. 6). FIG. 8 is a schematic diagram showing a part of the battery 110 (part indicated by II in FIG. 7) in an expanded manner. FIG. 9 is a schematic diagram of the assembled battery 110. In addition, about the common structure with the assembled battery 10 shown in FIG. 1 and FIG. 2, the same code | symbol is attached | subjected and description is abbreviate | omitted.

As shown in FIGS. 6 and 7, the assembled battery 110 is configured by stacking a plurality of battery units 11 (11A to 11G). The battery unit 11 includes a plurality of single cells 1, a battery outer package 2, and a bus bar 3 (see FIGS. 1 and 2). The battery unit 11 has substantially the same configuration as the assembled battery 10 shown in FIGS. 1 and 2.

As shown in FIGS. 7 and 9, in the battery unit 11 (battery unit 11A) of the first layer (uppermost layer), the positive electrode lead 55 of the cell 1 (cell 1A) is connected to the bus bar 3 (first layer bus bar 3A). ) Of the first conductive layer 32. The negative electrode lead 56 of the unit cell 1 (unit cell 1A) is electrically connected to the second conductive layer 34 of the bus bar 3 (first layer bus bar 3A).
One end portion of the second conductive layer 34 of the first layer bus bar 3A is connected to one end portion of the second conductive layer 34 of the second layer bus bar 3B and the connection portion 38 (first connection portion 38A). Is electrically connected.

In the second layer battery unit 11 (battery unit 11B), the positive electrode lead 55 of the unit cell 1 (unit cell 1B) is electrically connected to the second conductive layer 34 of the bus bar 3 (second layer bus bar 3B). ing. The negative electrode lead 56 of the unit cell 1 (unit cell 1B) is electrically connected to the first conductive layer 32 of the bus bar 3 (second layer bus bar 3B).
The other end portion of the first conductive layer 32 of the second layer bus bar 3B is connected to the other end portion of the first conductive layer 32 of the third layer bus bar 3C and the connection portion 38 (second connection portion 38B). Is electrically connected.

In the third layer battery unit 11 (battery unit 11C), the positive electrode lead 55 of the unit cell 1 (unit cell 1C) is electrically connected to the first conductive layer 32 of the bus bar 3 (third layer bus bar 3C). ing. The negative electrode lead 56 of the unit cell 1 (unit cell 1C) is electrically connected to the second conductive layer 34 of the bus bar 3 (third layer bus bar 3C).
One end portion of the second conductive layer 34 of the third layer bus bar 3C is connected to one end portion of the second conductive layer 34 of the fourth layer bus bar 3D and the connection portion 38 (third connection portion 38C). Is electrically connected.

In the battery unit 11 (battery unit 11D) of the fourth layer, the positive electrode lead 55 of the unit cell 1 (unit cell 1D) is electrically connected to the second conductive layer 34 of the bus bar 3 (fourth layer bus bar 3D). ing. The negative electrode lead 56 of the unit cell 1 (unit cell 1D) is electrically connected to the first conductive layer 32 of the bus bar 3 (fourth layer bus bar 3D).

As shown in FIG. 8, the assembled battery 110 can expand a plurality of stacked battery units 11.

The assembled battery 110 can have a structure in which a plurality of battery units 11 including a plurality of single cells 1 arranged in parallel are prepared and the plurality of battery units 11 are arranged in series. For example, in the assembled battery 110, as shown in FIGS. 6 and 9, three unit cells 1 (battery group) constituting the battery unit 11 are connected in parallel by the bus bar 3. The seven battery units 11 are connected in series.

1 and 2, a plurality of single cells 1 are connected in parallel by a bus bar 3. In the assembled battery 110 shown in FIGS. 6 and 9, the plurality of single cells 1 are connected in parallel and in series by the bus bars 3. Thus, the bus bar 3 can correspond to a plurality of connection forms. Further, since the bus bar 3 has a simple structure, the work of connecting the plurality of single cells 1 is facilitated. The bus bar 3 can be easily assembled because the leads 55 and 56 of the unit cell 1 can be connected from the same surface side (upper surface side in FIG. 1).

FIG. 10 is a configuration diagram of an assembled battery 210 which is still another example of the assembled battery using the bus bar 3. In addition, about the common structure with the already assembled battery, the same code | symbol is attached | subjected and description is abbreviate | omitted.
As shown in FIG. 10, the assembled battery 210 includes a plurality of battery units 11 and a heat diffusion sheet 12. The thermal diffusion sheet 12 is provided between the

battery units

11 and 11 adjacent to each other in the thickness direction (Z direction). The thermal diffusion sheet 12 includes, for example, a carbon-based material such as graphite. The thermal diffusion sheet 12 is preferably a graphite sheet. The thickness of the graphite sheet is preferably 10 to 1000 μm per monolayer, for example.

Examples of the characteristics of the graphite sheet include a thermal conductivity in the plane direction of 100 to 3000 W / (m · K) and a thermal conductivity in the thickness direction of 1 to 30 W / (m · K). Examples of methods for measuring thermal conductivity include ASTM D5470, ASTM E1530, JIS R2616, ASTM D5930, and JIS R1611.

The thermal diffusion sheet 12 has a thermal conductivity higher than that of the exterior plate 6 (specifically, the substrate portion 11). Therefore, the heat diffusion sheet 12 can diffuse the heat generated in the unit cell 1 in the in-plane direction. Therefore, the temperature rise of the single cell 1 at the time of electricity supply can be suppressed, and the temperature difference between the several single cells 1 can be made small.

FIG. 11 is an exploded perspective view showing an example of a connection structure between the

leads

55 and 56 of the unit cell 1 and the bus bar 3. FIG. 12 is an exploded plan view showing the connection structure. As shown in FIG. 11 and FIG. 12, this connection structure includes a bus bar 3, a pair of adhesive resin films 21 (adhesive resin layer), leads 55 and 56, a lead sealing layer 22, and a cover film 23. And comprising.

The adhesive resin film 21 is attached to the upper surface of the bus bar 3. The adhesive resin film 21 is made of an adhesive resin such as polyolefin (polypropylene, polyethylene, etc.), polyurethane, or polyether. The adhesive resin film 21 is formed in a rectangular frame shape, for example. Reference numeral 24 denotes an opening of the adhesive resin film 21. The opening 24 has a rectangular shape, for example. The adhesive resin film 21 surrounds at least a part of a connection portion between the

leads

55 and 56 and the

energization portions

41 and 42 in a plan view. The two

adhesive resin films

21 and 21 shown in FIGS. 11 and 12 are provided so as to surround the

tip portions

55a and 56a of the

leads

55 and 56, respectively. The outer shape of the adhesive resin film 21 is preferably a rectangular shape that is slightly larger than the energizing

portions

41 and 42 in plan view. Most of the area of the adhesive resin film 21 is overlaid on the energizing

portions

41 and 42. The adhesive resin film 21 is preferably fixed to the upper surface of the bus bar 3 by heat fusion or the like.

As shown in FIG. 12, the

leads

55 and 56 are installed on the upper surfaces of the current-carrying

portions

41 and 42 and the adhesive resin film 21. In a plan view, the

tip portions

55 a and 56 a of the

leads

55 and 56 are located in the opening 24 and contact the first energization portion 41.

Proximal end portions

55c and 56c of the extended portions 55b and 56b of the leads 55 and 56 (portions extending from the container 51) are in contact with the upper surface of the adhesive resin film 21.

As shown in FIGS. 11 and 12, the lead sealing layer 22 is formed in, for example, a rectangular shape whose length direction is along the X direction. As shown in FIG. 12, the lead sealing layer 22 is formed on both sides of the

base end portions

55c and 56c of the

leads

55 and 56 and the partial region 21a of the adhesive resin film 21 (

base end portions

55c and 56c). The adjacent adhesive resin film 21 part) is covered. The

base end portions

55c and 56c of the

leads

55 and 56 are portions of a certain length range including the base ends 55b1 and 56b1 of the extended portions 55b and 56b. The lead sealing layer 22 is made of, for example, a polyolefin resin (polypropylene, polyethylene, or the like) or a polyester resin.

The cover film 23 is made of, for example, an adhesive resin such as polyolefin (polypropylene, polyethylene, etc.), polyurethane, or polyether. The cover film 23 is, for example, a rectangular shape whose length direction is along the X direction, and has a length that can cover the two current-carrying

portions

41 and 42 at once. The cover film 23 covers the extended portions 55 b and 56 b of the

leads

55 and 56, the energizing

portions

41 and 42, the adhesive resin film 21, and the front portion 22 a of the lead sealing layer 22. The front portion 22 a is a portion including the side edge 22 b on the lead tip direction side in the lead sealing layer 22, and is a belt-like portion along the length direction of the lead sealing layer 22. The front portion 22 a overlaps the adhesive resin film 21. The cover film 23 is preferably joined to the extended portions 55b and 56b, the energizing

portions

41 and 42, the adhesive resin film 21, and the front portion 22a by heat fusion, adhesion, or the like. The cover film 23 is made of, for example, a polyester resin or a polyolefin resin (polypropylene, polyethylene, etc.).

The connection structure has the following effects. As shown in FIGS. 4 and 5, the first conductive layer 32 and the second conductive layer 34 of the bus bar 3 are not necessarily made of the same material as that of the

leads

55 and 56 to be connected. It is known that the contact location of dissimilar metals is likely to corrode when exposed to water.
As shown in FIGS. 11 and 12, in the connection structure, the extended portions 55b and 56b of the

leads

55 and 56, the energizing

portions

41 and 42, the adhesive resin film 21, and the front portion 22a of the lead sealing layer 22 are used. Since the cover film 23 is provided, the water or the outside air can be prevented from entering the connecting portions between the

leads

55 and 56 and the energizing

portions

41 and 42. Therefore, even when the leads 55 and 56 and the

conductive layers

32 and 34 are made of different metal materials, it is possible to prevent the occurrence of corrosion at the connection points.

In the connection structure, since the adhesive resin film 21 surrounding at least a part of the connection portion between the

leads

55 and 56 and the

energization portions

41 and 42 is provided, the cover film 23 surrounding the connection portion is attached to the adhesive resin film. 21 can reliably adhere to the energizing

portions

41 and 42. Therefore, it is possible to prevent water or outside air from entering the connection portion between the

leads

55 and 56 and the

energization units

41 and 42. Therefore, generation | occurrence | production of the corrosion in the said connection location can be prevented.

The

base end portions

55 c and 56 c of the

leads

55 and 56 are covered with the lead sealing layer 22. A front portion 22 a of the lead sealing layer 22 is covered with a cover film 23. Therefore, the extended portions 55 b and 56 b of the

leads

55 and 56 are almost entirely covered with the cover film 23 and the lead sealing layer 22. Therefore, the

leads

55 and 56 can be prevented from coming into contact with water or the outside air, and the corrosion of the

leads

55 and 56 can be prevented.

The cover film 23 shown in FIGS. 11 and 12 is formed so as to collectively cover the two

energization parts

41 and 42, but the cover film is configured to individually cover the two

energization parts

41 and 42. It may be. The adhesive resin film only needs to have a shape that can surround at least a part of the connection portion between the lead and the current-carrying portion, and may be, for example, an annular shape.

FIG. 13 is a diagram schematically illustrating an example of an electric device using the assembled battery 10.
Electric device 400 is a vehicle that can be moved by drive mechanism 401. Electric device 400 includes a vehicle body 402 and wheels 403. The drive mechanism 401 is a motor or the like that is operated by power supply from the assembled battery 10 and drives the wheels 403. The vehicle body 402 carries the drive mechanism 401 and the assembled battery 10.
The electric device may be an electric motorcycle, an electric bicycle, a robot, an electric wheelchair, an agricultural machine, an escalator, a washing machine, a refrigerator, or the like.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.
In the assembled battery shown in FIG. 2, the

exterior plates

6 and 6 are all formed continuously in the width direction across the plurality of cylindrical portions 14, but only one of the facing exterior plates is the exterior plate. The plurality of cylindrical portions may be formed continuously in the width direction, and the other exterior plate may be configured independently for each cylindrical portion.

The shape of the cylindrical part of the battery outer body is not limited to a hexagonal cylindrical shape. For example, if the first exterior plate constituting the battery exterior body has a substrate portion and a pair of side plate portions, and the second exterior plate has a flat plate shape with no inclination or unevenness, the cylindrical portion has a square shape. It becomes cylindrical. When the pair of side plate portions of the first exterior plate is inclined so as to approach the second exterior plate while being widened, the tubular portion becomes a trapezoidal tubular shape. In this battery exterior body, the bus bar can be disposed in contact with the second exterior plate. This battery exterior body is preferable from the viewpoint of ease of processing of the exterior plate because the second exterior plate has a flat plate shape.

FIG. 14 is a perspective view of an assembled battery 10 </ b> A that is a modification of the assembled battery 10. Of the pair of

exterior plates

106 and 106 constituting the battery exterior body 102, the first exterior plate 106 </ b> A is the same as the first exterior plate 6 </ b> A shown in FIG. 1, and the side plate inclined to the substrate unit 11.

Parts

12 and 12. The second exterior plate 106B is formed in a flat plate shape. The bus bar 3 is overlaid on the second exterior plate 106B. The cylindrical portion 114 of the battery exterior body 102 has a trapezoidal cylindrical shape.

In the bus bar 3 shown in FIG. 5, the second notch 37 exposing the second energizing portion 42 is formed in the resin layers 31 and 33 and the conductive layer 32, but the bus bar of the embodiment is limited to this structure. Not.
FIG. 15 is an exploded perspective view of the bus bar 103 according to the second embodiment. The bus bar 103 is different from the bus bar 3 shown in FIG. 5 in that a second notch 137 is formed instead of the second notch 37. The second notch 137 is formed in the third resin layer 35. In this embodiment, a plurality of second notches 137 are formed in the third resin layer 35. The plurality of second notches 137 are formed at intervals in the length direction of the bus bar 103.
The second notch 137 can have a rectangular shape when viewed from the thickness direction (Z direction) of the bus bar 103. The second notch 137 starts from the first side edge of the third resin layer 35 (the side edge overlapping the first side edge 31b of the first resin layer 31) toward the second side edge. It is formed in a concave shape. The second notch 137 exposes the second energization part 142 that is a part of the second conductive layer 34. The second energization part 142 is a partial region of the first surface 34 a of the second conductive layer 34.
The bus bar 103 has an advantage that it is easy to manufacture because the structure of the second notch 137 is simple.

In the bus bar 3 shown in FIG. 5, the first notch 36 is formed in the first resin layer 31 and the second notch 37 is formed in the resin layers 31, 32 and the resin layer 33. The bus bar is not limited to this structure. For example, the first notch may be formed in the second resin layer 33, the second conductive layer 34, and the third resin layer 35. In this case, the first current-carrying part exposed by the first notch is a part of the first surface 32 a of the first conductive layer 32. The second notch may be formed in the third resin layer 35. In this case, the second current-carrying part exposed by the second notch is a part of the first surface 34 a of the second conductive layer 34.

The bus bar of the embodiment includes a first and second conductive layers (

conductive layers

32 and 34 in the first embodiment), a main insulating layer (resin layer 33 in the first embodiment), and two covering insulating layers (first In one embodiment, the resin layers 31 and 35) have a basic configuration. The main insulating layer separates the first and second conductive layers. The main insulating layer is sandwiched between the inner surface of the first conductive layer and the inner surface of the second conductive layer. The covering insulating layer covers the outer surfaces of the first and second conductive layers (the surface opposite to the surface on the main insulating layer side).

The first energization part may be a part of the inner surface of the first conductive layer or a part of the outer surface. When the first energization part is a part of the inner surface of the first conductive layer, the first notch includes a main insulating layer, a second conductive layer, and a covering insulating layer covering the second conductive layer. Formed. When the first energization part is a part of the outer surface of the first conductive layer, the first notch is formed in the covering insulating layer covering the first conductive layer.
The second energization part may be a part of the inner surface of the second conductive layer or a part of the outer surface. When the second energization part is a part of the inner surface of the second conductive layer, the second notch includes a main insulating layer, a second conductive layer, and a covering insulating layer covering the second conductive layer. Formed. When the second energization part is a part of the outer surface of the second conductive layer, the second notch is formed in the covering insulating layer covering the second conductive layer.

In the bus bar 3 shown in FIG. 5, the first notch 36 is formed in the first resin layer 31 and the second notch 37 is formed in the resin layers 31, 32 and the resin layer 33. The bus bar is not limited to this structure. For example, the main insulating layer (second resin layer 33 in the first embodiment) is not limited to a single layer structure, and may have a multilayer structure. The conductive layers (the first conductive layer 32 and the second conductive layer 34) and the covering insulating layers (the first resin layer 31 and the third resin layer 35) may each have a multilayer structure.

1,1A, 1B, 1C, 1D cell (battery)
2,102 Battery

outer body

3, 3A, 3B, 3C,

3D Busbar

6, 6A, 6B, 106A, 106B Outer plate 7

Abutting part

10, 10A, 110, 210

Battery pack

14, 114 Cylindrical part 31 First Resin layer (first insulating layer)
32 1st conductive layer 33 2nd resin layer (2nd insulating layer)
34 Second conductive layer 35 Third resin layer (third insulating layer)
36 1st notch 37,137 2nd notch 41 1st electricity supply part 42,142 2nd electricity supply part 55 Positive electrode lead (1st electrode terminal)
56 Negative lead (second electrode terminal)
400 Electric Device 401 Drive Mechanism

Claims

A bus bar electrically connected to a battery having a first electrode terminal and a second electrode terminal,
The first insulating layer, the first conductive layer, the second insulating layer, the second conductive layer, and the third insulating layer are stacked in this order;
A part of the first conductive layer is exposed as a first current-carrying portion that can be electrically connected to the first electrode terminal,
A part of said 2nd conductive layer is a bus bar exposed as a 2nd electricity supply part which can be electrically connected with the said 2nd electrode terminal.
A first notch that exposes the first energization portion is formed in the first insulating layer;
The bus bar according to claim 1, wherein a second notch for exposing the second current-carrying portion is formed in the first insulating layer, the first conductive layer, and the second insulating layer.
A first notch that exposes the first energization portion is formed in the first insulating layer;
2. The bus bar according to claim 1, wherein a second notch for exposing the second energization portion is formed in the third insulating layer.
A bus bar according to any one of claims 1 to 3, and a plurality of the batteries,
At least one of the first electrode terminals is electrically connected to the first energization unit,
An assembled battery in which at least one of the second electrode terminals is electrically connected to the second energization unit.
The assembled battery according to claim 4, wherein the battery has a flat shape.
The battery includes a battery body, and a container having an internal space for housing the battery body,
6. The assembled battery according to claim 4, wherein the container is constituted by a laminated body in which a metal layer and a resin layer are laminated, and the resin layer is directed toward the internal space.
The battery further includes a battery outer body that covers the battery,
The battery exterior body includes at least a pair of facing exterior plates,
The exterior plates abut each other at a plurality of abutting portions at intervals in the width direction,
The assembled battery according to any one of claims 4 to 6, wherein the battery is accommodated in each of a plurality of cylindrical portions partitioned by the contact portion.
A thermal diffusion sheet in contact with two or more of the plurality of batteries via the battery outer package,
The assembled battery according to claim 7, wherein the thermal diffusion sheet has a thermal conductivity higher than a thermal conductivity of a contacted surface of the battery exterior body.
The assembled battery according to any one of claims 4 to 8,
And a driving mechanism driven by the assembled battery.