JPWO2019182117A1 - Busbars, batteries, and electric devices - Google Patents

Abstract

The busbar 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 part of the first conductive layer is exposed as a first energizing portion that can be electrically connected to the first electrode terminal. A part of the second conductive layer is exposed as a second energizing portion that can be electrically connected to the second electrode terminal.

Description

The present invention relates to a bus bar, an assembled battery, and an electric device.
The present application claims priority based on Japanese Patent Application No. 2018-056556 filed in Japan on March 23, 2018, the contents of which are incorporated herein by reference.

As awareness of the environment 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 Patent Application Laid-Open No. 2000-357494

In a storage battery for an electric vehicle or the like, an assembled battery configured by connecting a plurality of single batteries (lithium ion battery or the like) is used in order to increase the capacity. A plurality of cell cells are connected in parallel or in series via, for example, a bus bar made of metal or the like. It is required that the busbar can be easily connected to the cell.

One aspect of the present invention is to provide a busbar, an assembled battery, and an electric device capable of easily connecting a plurality of cells constituting the assembled battery.

A first aspect of the present invention is a busbar 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 laminated in this order. A part of the first conductive layer is exposed as a first energizing portion that can be electrically connected to the first electrode terminal. A part of the second conductive layer is exposed as a second energizing portion that can be electrically connected to the second electrode terminal.

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

In a third aspect of the present invention, in the bus bar of the first aspect, a first notch for exposing the first energized portion is formed in the first insulating layer. The bus bar has a second notch formed in the third insulating layer to expose the second energized portion.

A fourth aspect of the present invention is an assembled battery including a 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 energizing portion. At least one of the second electrode terminals is electrically connected to the second energizing portion.

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

A sixth aspect of the present invention has the following configuration. In the assembled battery of the fourth or fifth aspect, the battery includes a battery body and an accommodating body having an internal space for accommodating the battery body. The accommodating body is composed of a laminated body in which a metal layer and a resin layer are laminated. The resin layer is directed to the side of the internal space.

A seventh aspect of the present invention further includes a battery exterior body that exteriorizes the battery in the assembled battery of any one of the fourth to sixth aspects. The battery exterior includes at least a pair of facing exterior plates. The exterior plates come into contact with each other at a plurality of contact portions at intervals in the width direction. The battery is housed in a plurality of tubular portions partitioned by the abutting portion.

An eighth aspect of the present invention further includes, in the assembled battery of the seventh aspect, a heat diffusion sheet that comes into contact with two or more of the plurality of batteries via the battery exterior. The heat diffusion sheet has a thermal conductivity higher than the thermal conductivity on the contacted surface of the battery exterior.

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

Another aspect of the present invention is a busbar 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. The first resin layer is formed with a first notch that exposes a first energized portion that is a part of the first conductive layer and can be electrically connected to the first electrode terminal. There is. A second resin layer, which is a part of the second conductive layer and can be electrically connected to the second electrode terminal, is connected to the first resin layer, the first conductive layer, and the second resin layer. A second notch is formed to expose the energized portion of the.

According to one aspect of the present invention, a plurality of cell cells constituting the assembled battery can be easily connected.

It is an exploded perspective view which shows the assembled battery using the bus bar of 1st Embodiment. It is a perspective view after assembling the assembled battery shown in FIG. It is a perspective view which shows the example of the cell cell used for the assembled battery shown in FIG. It is a perspective view of the bus bar and a cell shown in FIG. It is an exploded perspective view of the bus bar shown in FIG. It is a block diagram of another example of the assembled battery using the bus bar shown in FIG. It is a schematic diagram which shows by disassembling a part of the assembled battery shown in FIG. It is a schematic diagram which shows a part of the assembled battery shown in FIG. 6 developed. It is a schematic diagram of the assembled battery shown in FIG. It is a block diagram of still another example of the assembled battery using the bus bar shown in FIG. It is an exploded perspective view which shows the example of the connection structure of the reed of a cell and a bus bar. It is a top view which shows by disassembling the connection structure of FIG. It is a figure which shows typically the electric device of one Embodiment. It is a perspective view of the modified example of the assembled battery shown in FIG. It is an exploded perspective view of the bus bar of the 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 cell 1 used in the assembled battery 10.
As shown in FIGS. 1 and 2, the assembled battery 10 includes a plurality of cell cells 1 (batteries), a battery exterior body 2, and a bus bar 3.

The assembled battery 10 includes one or more battery exteriors 2. The assembled battery 10 shown in FIG. 1 includes one battery exterior 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-metal material (for example, resin). The metal constituting the exterior plate 6 may be, for example, copper, nickel, iron, stainless steel, aluminum, or an alloy containing one or more of these. Examples of the non-metallic material 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; and polyamide resins such as nylon (Ny). ; Polyethylene resin; Fluorine resin; Acrylic resin; Polypropylene resin and the like.

The exterior plate 6 may have a single-layer structure or a multi-layer 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 a plan view.

In FIGS. 1 and 2, the X direction is the width direction of the exterior plate 6. The Y direction is an extension 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. Planar view means viewing from the Z direction.

The exterior plates 6 and 6 facing each other are in contact with each other at the plurality of contact portions 7. The contact portion 7 is formed in a strip 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. The portion of the exterior plate 6 between the abutting 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 has a substrate portion 11 and a pair of side plate portions 12, 12 inclined with respect to the substrate portion 11.

The substrate portion 11 is formed, for example, along the XY plane. The inner surface of the substrate portion 11 of the first exterior plate 6A comes into surface contact with one surface of the 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 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 widened from both side edges of the substrate portion 11 and are inclined and extended so as to approach the exterior plate 6 on the mating side. The side plate portions 12 and 12 have a flat shape and are inclined at an angle θ1 (0 ° <θ1 <90 °) (see FIG. 1) with respect to the substrate portion 11.
The intermediate portion 8 has a bent shape that is convex in the direction away from the mating exterior plate 6 (outward) 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 exterior plates 6 and 6 facing each other form a hollow square tubular tubular portion 14. The internal space of the tubular portion 14 is the battery accommodating portion 15. The tubular portion 14 is partitioned by abutting portions 7, 7. The exterior plates 6 and 6 have two or more tubular portions 14 arranged in the width direction (X direction). The number of tubular 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 exterior 2 has three tubular portions 14. The exterior plates 6 and 6 are all formed continuously over the three tubular portions 14.

In the assembled battery 10 shown in FIG. 2, since the side plate portions 12 and 12 are inclined, the tubular portion 14 has a hexagonal tubular 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 inclined so as to approach the plate body on the other side while widening, and the other intermediate portion has a substrate portion and a plate on the other side while widening. When it has a pair of side plate portions inclined so as to approach the body, the shape of the tubular portion composed of the substrate portion and the side plate portions is a hexagonal tubular portion. It is preferable that the tubular portion has a hexagonal tubular shape because the strength of the battery exterior is improved.

The abutting portions 7 and 7 can also be adhered to each other by an adhesive layer 9 (see FIG. 1) composed of an adhesive. Examples of the adhesive for adhering the contact portions 7 and 7 include a polyolefin adhesive, a urethane adhesive, an epoxy adhesive, an acrylic adhesive, a urethane adhesive, a nylon adhesive, and a polyester adhesive. Agents and the like can be mentioned. The adhesive may be an insulating material.

In the battery exterior body 2 shown in FIG. 2, since a plurality of tubular portions 14 are arranged side by side in the width direction (X direction) of the exterior plate 6, a honeycomb in which the plurality of tubular portions 14 are regularly arranged. It is a state structure. The number of the battery exterior bodies 2 (pair of exterior plates 6, 6) may be 1, or may be 2 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 cell 1 includes a battery body 50 and an accommodating body 51. The container 51 has a tray-shaped container body 52 and a lid 53 that closes the opening of the container body 52. The accommodating body 51 has an internal space for accommodating the battery 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 is a positive electrode lead (first electrode terminal) connected to the electrode (positive electrode) of the battery body 50. Reference numeral 56 is 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 housing 51.

The battery body 50 includes, for example, a positive electrode plate (not shown), a positive electrode active material layer in contact with the positive electrode plate (not shown), a negative electrode plate (not shown), and a negative electrode active material layer in contact with the negative electrode plate (not shown). It has 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, for example, metal. The positive electrode active material layer contains a positive electrode active material such as a lithium-based material. The negative electrode active material layer contains a negative electrode active material such as a carbon-based material. The battery body 50 preferably has a flat shape and a constant thickness.

The container body 52 and the lid 53 constituting the container 51 may be composed of, for example, a laminated body 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 housing 51 is configured with the resin layer 58 facing the internal space side.
Although not shown, the laminate is formed on a metal layer, a first resin layer laminated on the first surface of the metal layer, and a second surface (the surface opposite to the first surface) of the metal layer. It may have a structure including a laminated second resin layer (that is, a resin layer / metal layer / resin layer structure). This structure is preferable from the viewpoint of processability and durability of the laminated body.

The cell 1 has a flat shape, and is housed in the battery housing portion 15 (see FIG. 2) of the battery exterior 2 with the thickness direction facing the Z direction. The flat shape of the cell 1 means that the thickness dimension (dimension in the Z direction) of the cell 1 is smaller than the dimension in the width direction (X direction) and the dimension in the extension direction (Y direction). .. Since the cell 1 has a flat shape, the assembled battery 10 can be made thinner.

As shown in FIG. 2, the cell 1 is housed in a plurality of (three in FIG. 2) tubular portions 14, respectively. Since the cell 1 is housed in the tubular portion 14, it is exteriorized by the battery exterior body 2. It is preferable that the cell 1 is housed in the tubular portion 14 so as to be freely put in and taken out.

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

The bus bar 3 is a sheet-like laminated body including three resin layers 31, 33, 35 and two conductive layers 32, 34. The bus bar is formed by laminating a plurality of resin layers and one or a plurality of conductive layers. The bus bar is a laminated body including a resin layer and a conductive layer, and the resin layer is arranged on the outermost surface side. The resin layer and the conductive layer are laminated alternately, for example. Since the bus bar is a sheet-like laminated body, it has an advantage that it is easy to process when manufacturing an assembled battery.

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

As shown in FIG. 4, the bus bar 3 is formed in a band 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 as each other.

The resin layers 31, 33, 35 may be wider than the conductive layers 32, 34. It is preferable that the width of the resin layers 31, 33, 35 is wider than the width of the conductive layers 32, 34 from the viewpoint of preventing a short circuit between the conductive layers 32, 34. The width of the conductive layer can be, for example, 3 to 50 mm, 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 can be easily performed.

The busbar 3 shown in FIGS. 4 and 5 is a busbar for an assembled battery to which a plurality of cells constituting the assembled battery can be easily connected. In addition to the assembled battery, an electronic circuit, an electronic device, and an electric device It can be used as a member of. 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-shaped and thin, and has an effect that it is easy to connect 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 containing two or more of them. 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. The base metal layer and the plating layer are composed of, for example, the above-mentioned metals. For example, the conductive layers 32 and 34 may have a structure including a base metal layer made of copper and a nickel-plated 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. As the constituent materials of the first conductive layer 32 and the second conductive layer 34, not only metal but also carbon material, conductive resin and the like can be considered, but metal is preferable in terms of conductivity.

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, 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), polybutylene terephthalate (PBT) and the like. Of these, a resin film having heat-sealing properties is preferable, and polyolefin (polyethylene, polypropylene, etc.) is preferable.

The resin layers 31, 33, and 35 are insulating layers having an insulating property. The resin film may be a non-stretched film, or may be a uniaxially stretched or biaxially stretched film. The thicknesses of the resin layers 31, 33, and 35 are not particularly limited, but can be, for example, about 10 to 500 μm, or about 100 to 300 μm. The materials and film thicknesses of the resin layers 31, 33, and 35 may be different for 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 is formed with one or more first notches 36. 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 semicircle, but it is preferably rectangular from the viewpoint of connection with the lead. As shown in FIG. 5, the first notch 36 is formed at a position including the first side edge 31b of the first resin layer 31. The first notch 36 is formed in a concave shape from the first side edge 31b toward the second side edge 31c. For example, the first notch 36 is formed by two opposing edges 36a, 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. It is a rectangular notch. As shown in FIG. 4, the width (dimension in the X direction) of the first notch 36 is the same as the width of the first lead (for example, the positive electrode lead 55) connected to the first energizing portion 41, or 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 energizing portion 41. The first energizing portion 41 is a partial region of the second surface 32b (the surface opposite to the first surface 32a) of the first conductive layer 32. The tip of the first reed (for example, the positive electrode lead 55) of the leads 55 and 56 of the cell 1 comes into contact with the first energizing unit 41. It is preferable that the tip end portion of the first reed is overlapped with the first energizing portion 41 and comes into surface contact with the first energizing portion 41. When the first reed comes into contact with the first energizing portion 41, the first conductive layer 32 and the first reed 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 the notch 31d of the first resin layer 31, the notch 32b of the first conductive layer 32, and the notch 33b 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 positioned so as to overlap each other. The second notch 37 is a general term for the notches 31d, 32b, 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 it is preferably rectangular from the viewpoint of connection with the lead. The second notch 37 is formed at a position including the first side edges of the resin layers 31, 33 and 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 has two opposing edges 31d1, 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. It is a rectangular notch formed by and. 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 greater than the width of the second lead (for example, the negative electrode lead 56 shown in FIG. 4) connected to the second energizing 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 energizing portion 42. The second energizing portion 42 is a partial region of the second surface 34b (the surface opposite to the first surface 34a) of the second conductive layer 34. The tip of the second reed (for example, the negative electrode lead 56) of the leads 55 and 56 of the cell 1 comes into contact with the second energizing unit 42. It is preferable that the tip end portion of the second reed is overlapped with the second energizing portion 42 and comes into surface contact with the second energizing portion 42. When the second reed comes into contact with the second energizing portion 42, the second conductive layer 34 and the second reed are electrically connected.

The positions of the first notch 36 and the second notch 37 in the length direction of the bus bar 3 are different from each other. As shown in FIG. 1, a plurality of notch groups 40 having one first notch 36 and one second notch 37 are formed in the bus bar 3. 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. It is preferable that the order of the first notch 36 and the second notch 37 is common to the plurality of notch groups 40. In FIG. 1, three first notches 36 and three second notches 37 are formed alternately in the length direction of the bus bar 3.

As shown in FIG. 2, it is preferable that the bus bar 3 is fixed by being sandwiched between the abutting portions 7 and 7 of the exterior plates 6 and 6. Further, as shown in FIG. 2, the bus bar 3 or the leads 55 and 56 can be arranged in a plane without being bent, but the bus bar 3 or the leads 55 and 56 can be bent to provide at least a part of the bus bar 3 as an exterior. It can also be stacked on the board 6.

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

FIG. 6 is a block diagram of the 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 assembled battery 110 (the part indicated by I in FIG. 6). FIG. 8 is a schematic view showing a part of the battery 110 (the portion shown by II in FIG. 7) in an expanded manner. FIG. 9 is a schematic view of the assembled battery 110. The common configuration with the assembled battery 10 shown in FIGS. 1 and 2 is designated by the same reference numerals and the description thereof will be 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 cell cells 1, a battery exterior body 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 (top layer), the positive electrode lead 55 of the cell 1 (cell 1A) is the bus bar 3 (first layer bus bar 3A). ) Is electrically connected to the first conductive layer 32. The negative electrode lead 56 of the cell 1 (cell 1A) is electrically connected to the second conductive layer 34 of the bus bar 3 (first layer bus bar 3A).
One end of the second conductive layer 34 of the first layer bus bar 3A is formed by connecting one end of the second conductive layer 34 of the second layer bus bar 3B and the connecting portion 38 (first connecting portion 38A). It is electrically connected via.

In the second layer battery unit 11 (battery unit 11B), the positive electrode lead 55 of the cell 1 (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 cell 1 (cell 1B) is electrically connected to the first conductive layer 32 of the bus bar 3 (second layer bus bar 3B).
The other end of the first conductive layer 32 of the second layer bus bar 3B has a connecting portion 38 (second connecting portion 38B) with the other end of the first conductive layer 32 of the third layer bus bar 3C. It is electrically connected via.

In the third layer battery unit 11 (battery unit 11C), the positive electrode lead 55 of the cell 1 (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 cell 1 (cell 1C) is electrically connected to the second conductive layer 34 of the bus bar 3 (third layer bus bar 3C).
One end of the second conductive layer 34 of the third layer bus bar 3C is formed by connecting one end of the second conductive layer 34 of the fourth layer bus bar 3D and the connecting portion 38 (third connecting portion 38C). It is electrically connected via.

In the fourth layer battery unit 11 (battery unit 11D), the positive electrode lead 55 of the cell 1 (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 cell 1 (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 also deploy a plurality of stacked battery units 11.

The assembled battery 110 may have a structure in which a plurality of battery units 11 including a plurality of single batteries 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, the three cell 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.

In the assembled battery 10 shown in FIGS. 1 and 2, a plurality of cell cells 1 are connected in parallel by a bus bar 3. In the assembled battery 110 shown in FIGS. 6 and 9, a plurality of cell cells 1 are connected in parallel and in series by a bus bar 3. In this way, the bus bar 3 can support a plurality of connection forms. Further, since the bus bar 3 has a simple structure, the work of connecting a plurality of cell cells 1 becomes easy. The bus bar 3 is easy to assemble because the leads 55 and 56 of the 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 an assembled battery using the bus bar 3. The same reference numerals are given to the common configurations with the existing assembled batteries, and the description thereof will be omitted.
As shown in FIG. 10, the assembled battery 210 includes a plurality of battery units 11 and a heat diffusion sheet 12. The heat diffusion sheet 12 is provided between the battery units 11 and 11 adjacent to each other in the thickness direction (Z direction). The heat diffusion sheet 12 contains, for example, a carbon-based material such as graphite. The heat diffusion sheet 12 is preferably a graphite sheet. The thickness of the graphite sheet is preferably, for example, 10 to 1000 μm per single layer.

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

The heat 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 by the cell 1 in the in-plane direction. Therefore, it is possible to suppress the temperature rise of the cell 1 when energized and reduce the temperature difference between the plurality of cell 1.

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

The adhesive resin film 21 is attached to the upper surface of the bus bar 3. The adhesive resin film 21 is composed of a polyolefin-based (polypropylene, polyethylene, etc.), polyurethane-based, or polyether-based adhesive resin. The adhesive resin film 21 is formed in a rectangular frame shape, for example. Reference numeral 24 is an opening of the adhesive resin film 21. The opening 24 is, for example, rectangular. The adhesive resin film 21 surrounds at least a part of the connection points between the leads 55 and 56 and the energized 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 slightly larger than the energized portions 41 and 42 in a plan view. Most of the region of the adhesive resin film 21 is overlapped with the current-carrying 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 so as to be overlapped on the upper surfaces of the energizing portions 41 and 42 and the adhesive resin film 21. In a plan view, the tip portions 55a and 56a of the leads 55 and 56 are located in the opening 24 and come into contact with the first energizing portion 41. The base end portions 55c and 56c of the extending portions 55b and 56b (the portions extending from the housing 51) of the leads 55 and 56 come into 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, for example, in a rectangular shape whose length direction is along the X direction. As shown in FIG. 12, the lead sealing layer 22 is provided on both sides of the base end portions 55c and 56c of the leads 55 and 56 and the partial regions 21a of the adhesive resin film 21 (base end portions 55c and 56c). (Part of the adjacent adhesive resin film 21) is covered. The base end portions 55c, 56c of the leads 55, 56 are portions of a certain length range including the base ends 55b1, 56b1 of the extension portions 55b, 56b. The lead sealing layer 22 is made of, for example, a polyolefin-based (polypropylene, polyethylene, etc.) or polyester-based resin.

The cover film 23 is made of, for example, an adhesive resin such as polyolefin-based (polypropylene, polyethylene, etc.), polyurethane-based, or polyether-based. The cover film 23 has, for example, a rectangular shape whose length direction is along the X direction, and has a length capable of collectively covering the two energizing portions 41 and 42. The cover film 23 covers the extending 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. The front portion 22a is a portion of the lead sealing layer 22 including a side edge 22b on the lead tip direction side, and is a band-shaped portion along the length direction of the lead sealing layer 22. The front portion 22a overlaps with the adhesive resin film 21. The cover film 23 is preferably bonded to the extending portions 55b, 56b, the energizing portions 41, 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-based or polyolefin-based (polypropylene, polyethylene, etc.) resin.

The connection structure has the following effects. As shown in FIGS. 4 and 5, the same material as that of the connected leads 55 and 56 is not always used for the first conductive layer 32 and the second conductive layer 34 of the bus bar 3. It is known that the connection points of dissimilar metals are prone to corrosion when exposed to water.
As shown in FIGS. 11 and 12, in the connection structure, the extending 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 Since the cover film 23 is provided to cover the above, it is possible to prevent water or outside air from entering the connection points between the leads 55 and 56 and the energized 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 portion.

Since the connection structure is provided with the adhesive resin film 21 that surrounds at least a part of the connection points between the leads 55 and 56 and the current-carrying portions 41 and 42, the cover film 23 that surrounds the connection points is an adhesive resin film. 21 can reliably adhere to the energized portions 41 and 42. Therefore, it is possible to prevent water or outside air from entering the connection points between the leads 55 and 56 and the energized portions 41 and 42. Therefore, it is possible to prevent the occurrence of corrosion at the connection point.

The base end portions 55c and 56c of the leads 55 and 56 are covered with the lead sealing layer 22. The front portion 22a of the lead sealing layer 22 is covered with the cover film 23. Therefore, almost the entire surface of the extending portions 55b and 56b of the leads 55 and 56 is 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 leads 55 and 56 can be prevented from being corroded.

The cover film 23 shown in FIGS. 11 and 12 is formed so as to collectively cover the two energizing portions 41 and 42, but the cover film is configured to individually cover the two energizing portions 41 and 42. It may be. The adhesive resin film may 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 showing an example of an electric device using the assembled battery 10.
The electric device 400 is a vehicle that can be moved by the drive mechanism 401. The electric device 400 includes a vehicle body 402 and wheels 403. The drive mechanism 401 is a motor or the like that operates by supplying power from the assembled battery 10, and drives the wheels 403. The vehicle body 402 is equipped with a drive mechanism 401 and an 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 embodiment, 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 over the plurality of tubular portions 14, but only one of the exterior plates facing each other is formed as the exterior plate. It may be formed continuously in the width direction over a plurality of tubular portions, and the other exterior plate may have an independent configuration for each tubular portion.

The shape of the tubular portion of the battery exterior is not limited to the hexagonal tubular shape. For example, if the first exterior plate constituting the battery exterior has a substrate portion and a pair of side plate portions, and the second exterior plate has a flat plate shape without inclination or unevenness, the tubular portion has a square shape. It becomes tubular. When the pair of side plate portions of the first exterior plate are inclined so as to approach the second exterior plate while widening, the tubular portion becomes a trapezoidal tubular portion. In this battery exterior, the busbar can be placed 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 the assembled battery 10A, which is a modified example of the assembled battery 10. Of the pair of exterior plates 106 and 106 constituting the battery exterior 102, the first exterior plate 106A is the same as the first exterior plate 6A shown in FIG. 1, the substrate portion 11 and the side plates inclined with respect to the substrate portion 11. It has parts 12 and 12. The second exterior plate 106B is formed in the shape of a flat plate. The bus bar 3 is superposed on the second exterior plate 106B. The tubular portion 114 of the battery exterior 102 has a trapezoidal tubular shape.

In the bus bar 3 shown in FIG. 5, the second notch 37 that exposes the second energizing portion 42 is formed in the resin layers 31, 33 and the conductive layer 32, but the bus bar of the embodiment is limited to this structure. Not done.
FIG. 15 is an exploded perspective view of the bus bar 103 of 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 in place 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 be rectangular 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) and faces the second side edge. It is formed in a concave shape. The second notch 137 exposes a second energizing portion 142 that is part of the second conductive layer 34. The second energizing portion 142 is a partial region of the first surface 34a 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 33. Busbars are 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 energizing portion exposed by the first notch is a part of the first surface 32a of the first conductive layer 32. The second notch may be formed in the third resin layer 35. In this case, the second energizing portion exposed by the second notch is a part of the first surface 34a of the second conductive layer 34.

The busbars of the embodiment include a first and second conductive layer (conductive layers 32 and 34 in the first embodiment), a main insulating layer (resin layer 33 in the first embodiment), and two coated insulating layers (first embodiment). In one embodiment, the basic configuration is a resin layer 31, 35). 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 coated 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), respectively.

The first energizing portion may be a part of the inner surface or a part of the outer surface of the first conductive layer. When the first energizing portion is a part of the inner surface of the first conductive layer, the first notch is the main insulating layer, the second conductive layer, and the coating insulating layer covering the second conductive layer. Is formed in. When the first energizing portion 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 energizing portion may be a part of the inner surface or a part of the outer surface of the second conductive layer. When the second energizing portion is a part of the inner surface of the second conductive layer, the second notch is the main insulating layer, the second conductive layer, and the coating insulating layer covering the second conductive layer. Is formed in. When the second energizing portion 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 33. Busbars are 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 but may have a multi-layer structure. The conductive layer (first conductive layer 32 and second conductive layer 34) and the coated insulating layer (first resin layer 31 and third resin layer 35) may also have a multilayer structure, respectively.

1,1A, 1B, 1C, 1D cell (battery)
2,102 Battery exterior 3,3A, 3B, 3C, 3D Busbar 6,6A, 6B, 106A, 106B Exterior plate 7 Contact part 10,10A, 110,210 Battery assembly 14,114 Cylindrical part 31 First Resin layer (first insulating layer)
32 First conductive layer 33 Second resin layer (second insulating layer)
34 Second conductive layer 35 Third resin layer (third insulating layer)
36 First notch 37,137 Second notch 41 First energizing part 42, 142 Second energizing part 55 Positive electrode lead (first electrode terminal)
56 Negative electrode lead (second electrode terminal)
400 Electric device 401 Drive mechanism

Claims (9)

A busbar that is electrically connected to a battery having a first electrode terminal and a second electrode terminal.
It 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 laminated in this order.
A part of the first conductive layer is exposed as a first energizing portion that can be electrically connected to the first electrode terminal.
A bus bar in which a part of the second conductive layer is exposed as a second energizing portion that can be electrically connected to the second electrode terminal. The first insulating layer is formed with a first notch that exposes the first energized portion.
The busbar according to claim 1, wherein a second notch for exposing the second energizing portion is formed in the first insulating layer, the first conductive layer, and the second insulating layer. The first insulating layer is formed with a first notch that exposes the first energized portion.
The bus bar according to claim 1, wherein a second notch for exposing the second energizing portion is formed in the third insulating layer. The bus bar according to any one of claims 1 to 3 and a plurality of the batteries are provided.
At least one of the first electrode terminals is electrically connected to the first energizing portion.
An assembled battery in which at least one of the second electrode terminals is electrically connected to the second energizing portion. The assembled battery according to claim 4, wherein the battery has a flat shape. The battery includes a battery body and an accommodating body having an internal space for accommodating the battery body.
The assembled battery according to claim 4 or 5, wherein the housing is composed of a laminated body in which a metal layer and a resin layer are laminated, and the resin layer is directed to the side of the internal space. A battery exterior body for exteriorizing the battery is further provided.
The battery exterior comprises at least a pair of facing exterior plates.
The exterior plates come into contact with each other at a plurality of contact portions at intervals in the width direction.
The assembled battery according to any one of claims 4 to 6, wherein the battery is housed in a plurality of tubular portions partitioned by the contact portion. A heat diffusion sheet, which comes into contact with two or more of the plurality of batteries via the battery exterior, is further provided.
The assembled battery according to claim 7, wherein the heat diffusion sheet has a thermal conductivity higher than the thermal conductivity on the contact surface of the battery exterior. The assembled battery according to any one of claims 4 to 8.
An electric device including a drive mechanism driven by the assembled battery.

Images