JP6950486B2 - Batteries and their outer containers - Google Patents

Description

The present invention relates to an assembled battery in which a battery array in which a plurality of cells are arranged side by side is sealed by an outer container, and the outer container thereof.

Conventional assembled batteries are disclosed in Patent Document 1. In this assembled battery, a battery array in which a plurality of cells are arranged side by side is hermetically sealed by an outer container. The cell has a positive electrode and a negative electrode, and the positive electrode of one adjacent cell and the negative electrode of the other cell are electrically connected in order to form a battery array.

As the outer container of the assembled battery of Patent Document 1, a resin container is considered to be suitable because insulation is required. The outer container is provided with a resin container body and a lid, and a partition wall for partitioning a cell is integrally formed in the container body. Further, it is disclosed that heat radiation fins may be provided on the outer surface of the container body, and that the container body is molded by injection molding.

Japanese Unexamined Patent Publication No. 2006-260975 (pages 5 to 12, FIG. 3)

However, according to the conventional assembled battery, since the outer container is made of a resin molded product formed by injection molding, there is a problem that the weight and volume of the assembled battery become large.

An object of the present invention is to provide an assembled battery and an outer container thereof that can be reduced in size and weight.

In order to achieve the above object, the present invention is a set including a battery array in which a plurality of cells having positive and negative electrodes are electrically connected and arranged side by side, and an outer container for sealing and exteriorizing the battery array. In a battery, the outer container is provided with a cylindrical portion formed in a cylindrical shape by a resin sheet having a heat-adhesive resin layer arranged on at least an inner surface, and a plurality of side surface portions erected from each side of a polygonal bottom surface portion. It also has a pair of end face sealing portions that seal both end faces of the cylindrical portion in the axial direction, the bottom surface portion is formed of a resin sheet, and the side surface portion is axially oriented from the bottom surface portion. It is characterized in that it extends outward and is thermally adhered to the inner surface of the tubular portion.

Further, the present invention is characterized in that, in the assembled battery having the above configuration, radial folding lines are provided on the bottom surface portion.

Further, the present invention is characterized in that, in the assembled battery having the above configuration, the outer side of the side surface portion in the axial direction is heat-bonded to the inner surface of the tubular portion, and the inner side is not adhered to the tubular portion. ..

Further, the present invention is characterized in that, in the assembled battery having the above configuration, the bottom surface portion and the side surface portion are formed by bending a resin sheet, and a heat-adhesive resin layer is provided on the outer surface of the side surface portion.

Further, in the assembled battery having the above configuration, the adjacent side surface portions are connected by a connecting piece bent from the side surface portion, and the connecting piece is folded in half by a folding line extending from a corner of the bottom surface portion. It is characterized by.

Further, the present invention is characterized in that, in the assembled battery having the above configuration, the bottom surface portion and the side surface portion are integrally molded products of a resin sheet.

Further, the present invention is characterized in that, in the assembled battery having the above configuration, the end face sealing portion is made of a cold-molded product of a resin sheet.

Further, in the assembled battery having the above configuration, the end face sealing portion has an annular portion and a skeleton portion composed of an integrally molded product of a plurality of columnar portions erected from the annular portion, and the bottom surface portion and the bottom surface portion and the skeleton portion. The side surface portion is formed by bending a resin sheet, and the bottom surface portion and the inner surface of the side surface portion are adhered to the skeleton portion, and a heat-adhesive resin layer is provided on the outer surface of the side surface portion. It is supposed to be.

Further, in the assembled battery having the above configuration, the side surface portion is formed by an annular frame portion of a resin molded product, and the bottom surface portion adheres to the side surface portion to close one opening surface of the frame portion. It is a feature.

Further, the present invention is characterized in that the inside of the outer container is depressurized in the assembled battery having the above configuration.

Further, the present invention is characterized in that the assembled battery having the above configuration includes an electrode cover having a plurality of grooves into which the positive electrode and the negative electrode are inserted and arranged on the battery array.

Further, the present invention is characterized in that, in the assembled battery having the above configuration, the electrode cover has a conductor arranged on the inner surface of the groove portion and a wiring pattern for electrically connecting the conductor in the predetermined groove portion.

Further, the present invention is an outer container for an assembled battery in which a plurality of cells having a positive electrode and a negative electrode are electrically connected to electrically connect and arrange a battery array arranged side by side in a sealed manner, and is formed in a cylindrical shape by a resin sheet. A pair of a tubular portion having a heat-adhesive resin layer on at least an inner surface and a plurality of side surface portions erected from each side of a polygonal bottom surface portion and sealing both end faces in the axial direction of the tubular portion. The bottom surface portion is formed of a resin sheet, and the side surface portion extends outward in the axial direction from the bottom surface portion and is thermally bonded to the inner surface of the cylindrical portion. It is supposed to be.

According to the present invention, since the outer container includes a tubular portion of the resin sheet and end face sealing portions for sealing both end faces in the axial direction of the tubular portion, it is possible to reduce the size and weight of the assembled battery. Further, since the side surface portion extends from the bottom surface portion of the resin sheet to the outside in the axial direction of the tubular portion and is heat-bonded to the inner surface of the tubular portion, the tubular portion and the side surface portion can be easily heat-bonded. .. In addition, since the gap between the wall surface of the storage chamber of the assembled battery and the assembled battery before the cell expands can be reduced, rattling of the assembled battery can be prevented and failure of the assembled battery due to vibration can be reduced.

Perspective view which shows the assembled battery of 1st Embodiment of this invention. An exploded perspective view showing the assembled battery of the first embodiment of the present invention. Sectional drawing which shows the layer structure of the resin sheet of the outer container of the assembled battery of 1st Embodiment of this invention. Sectional drawing which shows the cylindrical part of the outer container of the assembled battery of 1st Embodiment of this invention. Cross-sectional view showing a modified example of the cylindrical portion of the outer container of the assembled battery of the first embodiment of the present invention. Sectional drawing which shows the layer structure of the other resin sheet of the outer container of the assembled battery of 1st Embodiment of this invention. Top view showing the blank plate of the end face sealing part of the outer container of the assembled battery of 1st Embodiment of this invention. Perspective view which shows the end face sealing part of the outer container of the assembled battery of 1st Embodiment of this invention. Front sectional view showing a main part of the assembled battery of the first embodiment of the present invention. The plan view which shows the blank plate of the end face sealing part of the outer container of the assembled battery of 2nd Embodiment of this invention. Perspective view which shows the end face sealing part of the outer container of the assembled battery of 2nd Embodiment of this invention. Perspective view which shows the end face sealing part of the outer container of the assembled battery of 3rd Embodiment of this invention. Top view showing the blank plate of the end face sealing part of the outer container of the assembled battery of 3rd Embodiment of this invention. Perspective view which shows the end face sealing part of the outer container of the assembled battery of 4th Embodiment of this invention. Front sectional view showing the end face sealing portion of the outer container of the assembled battery of the fourth embodiment of the present invention. Front sectional view showing a modified example of the end face sealing portion of the outer container of the assembled battery of the fourth embodiment of the present invention. Top sectional view showing the inside of the assembled battery of the fifth embodiment of the present invention. Rear view showing one electrode cover of the assembled battery of 5th Embodiment of this invention. Front view showing the other electrode cover of the assembled battery of the fifth embodiment of the present invention. Top sectional view showing the inside of the assembled battery of the sixth embodiment of the present invention. Rear view which shows the electrode cover of the assembled battery of 6th Embodiment of this invention.

<First Embodiment>
An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show a perspective view and an exploded perspective view of the assembled battery of the first embodiment. The assembled battery 1 is a battery array 2 in which a plurality of cell cells 3 composed of secondary batteries are arranged side by side, and is sealed by an outer container 10 to be exteriorized.

In the cell 3, a battery element containing a positive electrode, a negative electrode, and an electrolyte (all not shown) is arranged inside a housing 4 formed of a laminated body such as a resin sheet. Positive electrodes 5 and negative electrodes 6 connected to the positive electrode and the negative electrode, respectively, project from the housing 4 at both ends of the cell 3. The positive electrode 5 and the negative electrode 6 are made of metal or the like. In this embodiment, the positive electrode 5 is made of aluminum and the negative electrode 6 is made of nickel.

In the battery array 2, a plurality of cell cells 3 having positive electrodes 5 and negative electrodes 6 arranged at both ends in the Y direction are arranged side by side in the X direction. The positive electrode 5 of the first cell 3 from the left shown in FIG. 2 projects forward, and the negative electrode 6 projects rearward. The positive electrode 5 of the second cell 3 from the left protrudes rearward, and the negative electrode 6 protrudes forward. The cell 3 is repeatedly arranged so that the positive electrode 5 and the negative electrode 6 project in the opposite directions in the Y direction in order.

A plurality of cells 3 are connected in series by electrically connecting the positive electrode 5 of one adjacent cell 3 and the negative electrode 6 of the other cell 3 in order by a lead wire (not shown), soldering, welding, or the like. NS. That is, the negative electrode 6 of the first cell 3 from the left in FIG. 2 and the positive electrode 5 of the second cell 3 adjacent to the negative electrode 6 are electrically connected. The negative electrode 6 of the second cell 3 from the left and the positive electrode 5 (not shown) of the third cell 3 (not shown) adjacent to the negative electrode 6 are electrically connected. Hereinafter, similarly, the electrical connection between the positive electrode 5 and the negative electrode 6 is repeated.

A terminal 7 extending in the X direction is connected to the positive electrode 5 at one end of the battery array 2 (the positive electrode 5 of the first cell 3 from the left in FIG. 2). A terminal 8 extending in the X direction is connected to the negative electrode 6 at the other end of the battery array 2 (the negative electrode 6 of the first cell 3 from the right in FIG. 2). The number of cells 3 forming the battery array 2 (4 in this embodiment) can be appropriately determined.

The outer container 10 has a cylindrical tubular portion 11 and a pair of end face sealing portions 21 that seal both end faces of the tubular portion 11 in the axial direction (X direction). The tubular portion 11 and the end face sealing portion 21 are formed of a resin sheet 50 (see FIG. 3). The battery array 2 is housed inside the tubular portion 11.

FIG. 3 is a cross-sectional view showing a laminated structure of the resin sheet 50. The resin sheet 50 is composed of a laminate in which a heat-adhesive resin layer 52, a base material layer 54, a barrier layer 56, and a heat-adhesive resin layer 58 are laminated in this order. The thickness of the resin sheet 50 is preferably 50 μm or more in consideration of strength, and 400 μm or less in consideration of miniaturization and weight reduction of the assembled battery 1.

The base material layer 54 has an insulating property and is formed of a resin film such as nylon, polyester, or polyethylene terephthalate. The base material layer 54 may be formed of a non-woven fabric of thermoplastic fibers. The thickness of the base material layer 54 is formed to be, for example, 10 μm or more and 75 μm or less. It is more desirable to form the base material layer 54 with a uniaxially stretched film or a biaxially stretched film in order to improve heat resistance.

Further, in order to improve pinhole resistance, insulating property, etc., a plurality of resin films made of different materials may be laminated to form the base material layer 54. In the present embodiment, polyethylene terephthalate (thickness 12 μm) and nylon (thickness 15 μm) are laminated to form a base material layer 54, and polyethylene terephthalate is arranged on the heat-adhesive resin layer 52 side. As a result, the resin sheet 50 of the present embodiment is laminated in the order of the heat-adhesive resin layer 52, polyethylene terephthalate (base material layer 54), nylon (base material layer 54), the barrier layer 56, and the heat-adhesive resin layer 58. ..

The barrier layer 56 is formed of a metal foil to prevent the intrusion of water vapor, oxygen, light and the like. As the metal forming the barrier layer 56, aluminum, aluminum alloy, stainless steel, titanium and the like can be used. The thickness of the barrier layer 56 is formed to be, for example, 10 μm or more and 300 μm or less. In this embodiment, the barrier layer 56 is formed of aluminum foil (thickness 80 μm). Since the sealed outer container 10 includes the barrier layer 56, the barrier layer may be omitted in the laminated structure of the resin sheets constituting the storage body 4 (see FIG. 2) of the cell 3.

The heat-adhesive resin layers 52 and 58 have heat-adhesive properties and are formed of a resin film such as polypropylene, acid-modified polypropylene, low-density polyethylene, or linear low-density polyethylene. A plurality of resin films of different materials may be laminated to form the heat-adhesive resin layers 52 and 58. The thickness of the heat-adhesive resin layers 52 and 58 is formed to be, for example, 10 μm or more and 80 μm or less.

In the present embodiment, the heat-adhesive resin layer 52 is formed of acid-modified polypropylene (thickness 40 μm). Further, acid-modified polypropylene (thickness 40 μm) and polypropylene (thickness 40 μm) are laminated to form a heat-adhesive resin layer 58, and acid-modified polypropylene is arranged on the barrier layer 56 side.

The base material layer 54 and the barrier layer 56 are adhered to each other by an adhesive (not shown) such as polyurethane or acrylic. The heat-adhesive resin layer 52 is formed on the base material layer 54 by extrusion molding, and the heat-adhesive resin layer 58 is formed on the barrier layer 56 by extrusion molding. The heat-adhesive resin layer 52 and the base material layer 54 may be adhered with an adhesive, or the barrier layer 56 and the heat-adhesive resin layer 58 may be adhered with an adhesive.

FIG. 4 shows a cross-sectional view of the cylindrical portion 11 perpendicular to the X direction (see FIG. 2). The tubular portion 11 is formed by sticking a so-called envelope. That is, the resin sheet 50 in which the heat-adhesive resin layer 52 is arranged on the inner surface side is formed in a tubular shape, and the heat-adhesive portion 11a in which the heat-adhesive resin layer 52 and the heat-adhesive resin layer 58 are heat-bonded to each other is peripheral. Formed on the surface.

The tubular portion 11 may be formed by sticking the resin sheet 50 together. FIG. 5 shows a cross-sectional view of the tubular portion 11 of this modified example perpendicular to the X direction (see FIG. 2). In the tubular portion 11, a resin sheet 50 in which a heat-adhesive resin layer 52 is arranged on the inner surface side is formed in a tubular shape with a rectangular cross section, and a heat-bonded portion 11a in which the opposite heat-adhesive resin layers 52 are heat-bonded is from the peripheral surface. It is formed protruding.

The heat-adhesive resin layer 52 is arranged on the inner surface of the tubular portion 11, and the heat-adhesive resin layer 52 is arranged on the outer surface of the end face sealing portion 21 as described later. As a result, the acid-modified polypropylene forming the heat-adhesive resin layer 52 has adhesiveness to the metal terminals 7 and 8, so that the outer container 10 can be reliably sealed.

When the heat-adhesive resin layer 52 is made of a material different from that of acid-modified polypropylene (for example, polypropylene), the outer container 10 can be sealed by covering the terminals 7 and 8 with a tab seal made of acid-modified polypropylene. Similarly, when the heat-adhesive resin layer 58 is arranged on the inner surface of the tubular portion 11 and the heat-adhesive resin layer 58 is arranged on the outer surface of the end face sealing portion 21, which will be described later, the tab seal is also used. It will be.

As shown in FIG. 6, the tubular portion 11 of FIG. 5 and the tubular portion 11 described later are provided by the resin sheet 51 in which the heat-adhesive resin layer 52 is omitted and the base material layer 54, the barrier layer 56, and the heat-adhesive resin layer 58 are laminated. The end face sealing portion 21 of FIG. 8 may be formed. At this time, it is more desirable that the acid-modified polypropylene is arranged on the exposed surface of the heat-adhesive resin layer 58.

FIG. 7 shows a plan view of the blank plate 60 of the end face sealing portion 21 made of the resin sheet 50. The end face sealing portion 21 is formed by bending a blank plate 60 on each folding line 61. A radial fold line 62a is provided on the rectangular bottom plate 62. A side plate 63a, a reinforcing plate 63b, and a folded piece 64a are continuously provided on one of the two opposite sides of the bottom plate 62 via a folding line 61. A side plate 63c, a reinforcing plate 63d, and a folded piece 64c are continuously provided on the other two opposite sides of the bottom plate 62 via a folding line 61.

Flaps 65 are connected to both ends of the side plate 63a via folding lines 61. The length L1 of the flap 65 is slightly shorter than 1/2 of the length L2 of the side plate 63c in the longitudinal direction.

FIG. 8 shows a perspective view of the end face sealing portion 21 formed by the blank plate 60 of FIG. The side plates 63a and 63c are erected by being bent from the bottom plate 62, and the reinforcing plates 63b and 63d are folded back and stacked on the side plates 63a and 63c. The folded pieces 64a and 64c are folded back from the reinforcing plates 63b and 63d and arranged on the bottom plate 62. At this time, the folded piece 64a is arranged on the folded piece 64c. Further, the flap 65 bent from the side plate 63a is arranged between the side plate 63c and the reinforcing plate 63d.

As a result, the end face sealing portion 21 in which the side surface portion 23 is erected from each side of the rectangular bottom surface portion 22 made of the bottom plate 62 is formed. The side surface portion 23 is formed by superimposing reinforcing plates 63b and 63d on the side surface plates 63a and 63c. At this time, the heat-adhesive resin layer 52 (see FIG. 3) is arranged on the outer surface of the side surface portion 23. The heat-adhesive resin layer 58 (see FIG. 3) may be used for heat-bonding between the side plate 63a and the reinforcing plate 63b and between the side plate 63c and the reinforcing plate 63d.

FIG. 9 shows a front sectional view of a main part of the assembled battery 1. The battery array 2 is inserted inside the tubular portion 11. The length of the tubular portion 11 in the X direction is larger than the length of the battery array 2 in the X direction, and the tubular portion 11 has a protruding portion 11c protruding outward from the end surface of the battery array 2. The pair of end face sealing portions 21 are inserted into the openings at both ends of the tubular portion 11. At this time, the side surface portion 23 extends from the bottom surface portion 22 to the outside in the axial direction (X direction) of the tubular portion 11 and is arranged.

Then, the protruding portion 11c of the tubular portion 11 and the side surface portion 23 of the end face sealing portion 21 are sandwiched by a pair of heating tools 70, and the pressure is applied to heat as shown by the arrow A. As a result, the heat-adhesive resin layer 52 on the inner surface of the tubular portion 11 and the heat-adhesive resin layer 52 on the outer surface of the side surface portion 23 are heat-bonded, and the outer container 10 is sealed. At this time, the inside of the outer container 10 is evacuated to reduce the pressure.

Since the tubular portion 11 and the end face sealing portion 21 of the outer container 10 are formed of the resin sheet 50 having a small thickness, the assembled battery 1 can be reduced in size and weight. Further, since the side surface portion 23 extends outward from the bottom surface portion 22 in the X direction, the protrusion portion 11c and the side surface portion 23 can be easily heat-bonded by the heating tool 70.

The cell 3 may generate heat and expand during use. Since the battery array 2 has a plurality of cell cells 3 arranged side by side in the X direction, the amount of expansion in the X direction is large. At this time, the battery array 2 itself expands, but the inside of the outer container 10 is depressurized, so that the expansion of the outer container 10 due to the temperature rise of the gas in the outer container 10 is suppressed.

The bottom surface portion 22 of the end face sealing portion 21 faces the battery array 2 in the X direction and is formed of a flexible resin sheet 50. Therefore, even if the bottom surface portion 22 is arranged close to the battery array 2, the bottom surface portion 22 is curved as shown by the alternate long and short dash line D in FIG. 9 when the cell 3 expands. Therefore, the gap between the battery array 2 before the cell 3 expands and the bottom surface portion 22 of the end face sealing portion 21 can be reduced, and the assembled battery 1 can be further miniaturized.

In addition, since the side surface portion 23 extends outward from the bottom surface portion 22 in the X direction, the external dimensions of the assembled battery 1 change even if the bottom surface portion 22 inside the tip of the side surface portion 23 bends when the cell 3 expands. do not. Therefore, the gap between the wall surface of the storage chamber of the assembled battery 1 and the assembled battery 1 before the cell 3 expands can be reduced. Therefore, rattling of the assembled battery 1 can be prevented, and failure of the assembled battery 1 due to vibration can be reduced.

Further, since the radial folding line 62a (see FIG. 7) is formed on the bottom surface portion 22, the bottom surface portion 22 can be easily curved when the cell 3 is expanded. This makes it possible to prevent the outer container 10 from bursting. It is more desirable that the outside of the side surface portion 23 in the axial direction (X direction) is heat-bonded to the inner surface of the protrusion 11c, and the inside is non-bonded to the protrusion 11c. As a result, the bottom surface portion 22 can be more easily curved when the cell cell 3 is expanded.

According to the present embodiment, since the outer container 10 includes the tubular portion 11 of the resin sheet 50 and the end face sealing portions 21 that seal both end faces of the tubular portion 11 in the axial direction, the assembled battery 1 is compact and lightweight. Can be achieved.

Further, since the side surface portion 23 extends from the bottom surface portion 22 of the resin sheet 50 to the outside in the axial direction (X direction) of the tubular portion 11 and is heat-bonded to the inner surface of the tubular portion 11, the protruding portion of the tubular portion 11 The 11c and the side surface portion 23 can be easily heat-bonded. In addition, since the gap between the wall surface of the storage chamber of the assembled battery 1 and the assembled battery 1 before the expansion of the cell 3 can be reduced, rattling of the assembled battery 1 is prevented and the failure of the assembled battery 1 due to vibration is reduced. can do.

Further, since the radial folding line 62a is provided on the bottom surface portion 22, the bottom surface portion 22 can be easily curved when the cell 3 is expanded. Therefore, even if the cell 3 expands, the outer container 10 can be prevented from bursting due to the curvature of the bottom surface portion 22.

Further, the bottom surface portion 22 and the side surface portion 23 are formed by bending the resin sheet 50, and have a heat-adhesive resin layer 52 on the outer surface of the side surface portion 23. Thereby, the end face sealing portion 21 for sealing the tubular portion 11 can be easily realized.

Further, if the outer side of the side surface portion 23 in the axial direction (X direction) is heat-bonded to the inner surface of the tubular portion 11 and the inner surface is not adhered to the tubular portion 11, the bottom surface portion 22 is attached when the cell 3 expands. It can be easily curved. Further, since it is not necessary to arrange the heating tool 70 up to the inner end of the side surface portion 23 and heat-bond it, the heat-bonding work between the tubular portion 11 and the end face sealing portion 21 becomes easy.

Further, since the inside of the outer container 10 is depressurized, the expansion of the outer container 10 due to the temperature rise of the gas in the outer container 10 is suppressed.

<Second Embodiment>
Next, FIG. 10 is a plan view showing a blank plate 60 of the end face sealing portion 21 of the assembled battery 1 of the second embodiment. For convenience of explanation, the same parts as those in the first embodiment shown in FIGS. 1 to 9 described above are designated by the same reference numerals. In this embodiment, the reinforcing plates 63b and 63d, the folded pieces 64a and 64c and the flap 65 (see FIG. 7) are omitted, and the connecting piece 68 is provided. Other parts are the same as those in the first embodiment.

Side plates 63a are continuously provided on one of the two opposite sides of the rectangular bottom plate 62 via the folding line 61. Side plate 63c is continuously provided on the other two opposite sides of the bottom plate 62 via the folding line 61. The adjacent side plate 63a and the side plate 63c are connected by a rectangular connecting piece 68. A folding line 61a extending diagonally from the corner of the bottom plate 62 to the connecting piece 68 is provided on the connecting piece 68.

FIG. 11 shows a perspective view of the end face sealing portion 21 formed by the blank plate 60 of FIG. The side plates 63a and 63c are erected by bending from the bottom plate 62. The connecting piece 68 is bent inward from the side plate 63a and the side plate 63c and folded in half on the folding line 61a. As a result, the end face sealing portion 21 in which the side surface portions 23 formed by the side surface plates 63a and 63c are erected from each side of the rectangular bottom surface portion 22 made of the bottom plate 62 is formed.

At this time, the heat-adhesive resin layer 52 of the resin sheet 50 (see FIG. 3) is arranged on the outer surface of the side surface portion 23. The inner surface of the connecting piece 68 folded in half may be heat-bonded by the heat-adhesive resin layer 52. The heat-adhesive resin layer 58 (see FIG. 3) on the outer surface of the two-folded connecting piece 68 and the heat-adhesive resin layer 58 on the inner surface of the side surface portion 23 may be heat-bonded. Further, the end face sealing portion 21 may be formed from the resin sheet 51 (see FIG. 6), and the heat-adhesive resin layer 58 may be arranged on the outer surface of the side surface portion 23.

According to this embodiment, the same effect as that of the first embodiment can be obtained. Further, the rectangular connecting piece 68 connecting the side plates 63a and 63c is folded in half along the folding line 61a extending from the corner of the bottom surface portion 22. Therefore, it is possible to prevent the formation of a gap between the corner of the bottom surface portion 22 and the side surface portion 23. Therefore, the outer container 10 can be reliably sealed.

In the first and second embodiments, the bottom surface portion 22 and the side surface portion 23 are formed by bending the resin sheets 50 and 51 and further performing heat bonding as necessary, but the present invention is limited thereto. is not it. It suffices that the end face sealing portion 21 includes a bottom surface portion 22 and a side surface portion 23, and the outer surface of the end face sealing portion 21 has thermal adhesiveness.

Specifically, the bottom surface portion 22 and the side surface portion 23 may be integrally molded by cold-molding one resin sheet having the same laminated structure as the resin sheets 50 and 51. In this case, the end face sealing portion 21 is composed of a cold-molded product of one resin sheet.

For example, one resin sheet having the same laminated structure as the resin sheets 50 and 51 used in the first embodiment and the second embodiment is prepared. Next, in a molding die (female mold) having a diameter 1 to 2 mm larger than the vertical and horizontal size of the bottom surface portion 22, and a molding die (male mold) corresponding to this, the depth of the side surface portion 23 is 0.4 MPa. Cold mold. As a result, a recess is formed in the central portion of the molded product. By removing the flange region existing around the concave portion by cutting or punching, a cold molded product having only the concave portion is obtained. The cold-molded product having only the recess becomes the end face sealing portion 21 composed of the bottom surface portion 22 and the side surface portion 23.

As described above, the resin sheet 50 is composed of a laminate in which a heat-adhesive resin layer 52, a base material layer 54, a barrier layer 56, and a heat-adhesive resin layer 58 are laminated in this order. In the above manufacturing process, the heat-adhesive resin layer 52 is arranged to face the molding surface of the female mold, and the heat-adhesive resin layer 58 is arranged to face the molding surface of the male mold. The end face sealing portion 21 as a cold-molded product in which the heat-adhesive resin layer 52 is arranged can be formed.
By providing a radial groove in the female mold and providing a radial protrusion at a position corresponding to the male mold, it is possible to mold the radial fold line 62a at the same time. ..

The end face sealing portion 21 as the cold-molded product does not require bending of the resin sheets 50 and 51 and, if necessary, heat-bonding the overlapping resin sheets to each other. Therefore, since the manufacturing process is simplified, the manufacturing efficiency is good and the manufacturing cost can be suppressed, which is excellent.

Further, similarly to the above, it is also possible to heat-adhere the outside of the side surface portion 23 in the axial direction (X direction) to the inner surface of the tubular portion 11 and make the inside non-adhesive to the tubular portion 11. At this time, since the non-adhesive portion of the side surface portion 23 does not need to be adhered to the inner surface of the tubular portion 11, various variations are possible without having to be perpendicular to the bottom surface portion 22.

For example, the non-adhesive portion of the side surface portion 23 may have a tapered surface by forming a tapered surface toward the inside of the side surface portion 23 in the axial direction (X direction). As a result, the size of the adhesive portion of the side surface portion 23 can be matched with the size of the inner surface of the tubular portion 11, while the size of the bottom surface portion 22 can be reduced by 1 to 2 mm from the size of the inner surface of the tubular portion 11. be. By forming the end face sealing portion 21 having such a tapered structure, the insertion operation can be facilitated when the end face sealing portion 21 is inserted into the end face of the tubular portion 11 from the bottom surface portion 22.

Further, by adopting a bellows structure for the non-adhesive portion of the side surface portion 23, the non-adhesive portion of the side surface portion 23 can be expanded and contracted in the axial direction (X direction) of the side surface portion 23. By adopting such a bellows structure, the bottom surface portion 22 is arranged close to the battery array 2, and when the cell 3 expands, the non-adhesive portion of the side surface portion 23 shrinks due to the bellows structure, so that the bottom surface portion 22 becomes a side surface. It smoothly retracts in the axial direction (X direction) of the portion 23. Therefore, as in the case where the bottom surface portion 22 is curved as shown by the alternate long and short dash line D in FIG. 9, the gap between the battery array 2 before the cell 3 expands and the bottom surface portion 22 of the end face sealing portion 21. Can be made smaller, and the assembled battery 1 can be made smaller.

<Third Embodiment>
Next, FIG. 12 is a perspective view showing an end face sealing portion 21 of the assembled battery 1 of the third embodiment. For convenience of explanation, the same parts as those in the first embodiment shown in FIGS. 1 to 9 described above are designated by the same reference numerals. The end face sealing portion 21 of the assembled battery 1 of the present embodiment includes a skeleton portion 25 of a resin molded product and a resin sheet 50. Other parts are the same as those in the first embodiment.

The skeleton portion 25 is formed by injection molding and has an annular portion 25a and a columnar portion 25b that are integrally molded. The annular portion 25a is formed in a rectangular ring shape, and the columnar portion 25b is erected from each corner of the annular portion 25a. Polypropylene or the like can be used as the material for forming the skeleton portion 25. In FIG. 12, the skeleton portion 25 is depicted in a thick prismatic shape in order to make the invention easier to understand, but it is actually formed in a needle shape having a diameter of about 1 to 2 mm.

FIG. 13 is a plan view showing a blank plate 60 of the resin sheet 50 (see FIG. 3) bonded to the skeleton portion 25. Side plates 63a are continuously provided on one of the two opposite sides of the rectangular bottom plate 62 via the folding line 61. Side plate 63c is continuously provided on the other two opposite sides of the bottom plate 62 via the folding line 61.

The peripheral portion of the bottom plate 62 of the blank plate 60 of FIG. 13 and the peripheral portions of the side plates 63a and 63c are heat-bonded to the skeleton portion 25 by the heat-adhesive resin layer 58 (see FIG. 3). As a result, the end face sealing portion 21 in which the side surface portions 23 formed by the side surface plates 63a and 63c are erected from each side of the rectangular bottom surface portion 22 made of the bottom plate 62 is formed. A heat-adhesive resin layer 52 (see FIG. 3) is arranged on the outer surface of the side surface portion 23.

The skeleton portion 25 and the resin sheet 50 may be adhered to each other with an adhesive. At this time, the heat-adhesive resin layer 58 (see FIG. 6) may be arranged on the outer surface of the side surface portion 23 using the resin sheet 51 (see FIG. 6).

According to the present embodiment, since the outer container 10 excluding the skeleton portion 25 is formed of the resin sheet 50, the assembled battery 1 can be made smaller and lighter, and the same effect as that of the first embodiment can be obtained. Further, since the end face sealing portion 21 is formed by adhering the resin sheet 50 to the skeleton portion 25 of the resin molded product, the end face sealing portion 21 for sealing the tubular portion 11 can be easily realized.

<Fourth Embodiment>
Next, FIGS. 14 and 15 are a perspective view and a front sectional view showing an end face sealing portion 21 of the assembled battery 1 of the fourth embodiment. For convenience of explanation, the same parts as those in the first embodiment shown in FIGS. 1 to 9 described above are designated by the same reference numerals. The end face sealing portion 21 of the assembled battery 1 of the present embodiment includes a frame portion 26 of a resin molded product and a resin sheet 50. Other parts are the same as those in the first embodiment.

The frame portion 26 is formed into a rectangular annular shape by injection molding. Polypropylene or the like can be used as the material for forming the frame portion 26. The peripheral edge of the resin sheet 50 is heat-bonded to the inner surface of the frame portion 26 by the heat-adhesive resin layer 52 (see FIG. 3) to close one opening surface of the frame portion 26. As a result, the end face sealing portion 21 on which the side surface portion 23 formed by the frame portion 26 of the resin molded product stands up from each side of the rectangular bottom surface portion 22 made of the resin sheet 50 is formed.

The end face sealing portion 21 is inserted into the tubular portion 11 as shown in FIG. 2, and the frame portion 26 is heat-bonded to the inner surface of the tubular portion 11 by the heat-adhesive resin layer 52 (see FIG. 3).

The resin sheet 50 may be heat-bonded to the frame portion 26 with an adhesive. Further, the resin sheet 51 (see FIG. 6) may be heat-bonded to the frame portion 26 by the heat-adhesive resin layer 58.

Further, as shown in the modified example of FIG. 16, an annular flange portion 26a projecting inward may be provided on one surface of the frame portion 26, and a rectangular resin sheet 50 may be adhered to the inner surface of the flange portion 26a. As a result, the opening 26b surrounded by the flange portion 26a is closed by the resin sheet 50.

According to the present embodiment, since the outer container 10 excluding the frame portion 26 is formed of the resin sheet 50, the assembled battery 1 can be made smaller and lighter, and the same effect as that of the first embodiment can be obtained. Further, since the end face sealing portion 21 is formed by adhering the resin sheet 50 to the frame portion 26 of the resin molded product, the end face sealing portion 21 for sealing the tubular portion 11 can be easily realized.

Further, also in the present embodiment, it is possible to provide a bellows structure on the side surface portion 23 in the same manner as described above. For example, in the end face sealing portion 21 in FIG. 15, the frame portion 26 and the resin sheet 50 are adhered to each other, and the bottom surface portion 22 is formed on one end surface of the frame portion 26 forming the side surface portion 23 in the X direction. At this time, by extending the resin sheet 50 further in the X direction from the portion where the frame portion 26 and the resin sheet 50 are adhered to each other, a portion of only the resin sheet 50 can be formed on the side surface portion 23. Only the resin sheet 50 of the side surface portion 23 can have a bellows structure.

In the modified example of FIG. 16, the resin sheet 50 can be further extended in the X direction from the opening of the flange portion 26a to form a portion of only the resin sheet 50 on the side surface portion 23. Only the resin sheet 50 of the side surface portion 23 can have a bellows structure.

By adopting such a bellows structure, the bottom surface portion 22 is arranged close to the battery array 2 as in the case described in the first and second embodiments, and when the cell cell 3 expands, the side surface portion 23 is not formed. As the bonded portion shrinks due to the bellows structure, the bottom surface portion 22 smoothly retracts in the axial direction (X direction) of the side surface portion 23. Therefore, the gap between the battery array 2 before the cell 3 expands and the bottom surface portion 22 of the end face sealing portion 21 can be reduced, and the assembled battery 1 can be further miniaturized.

<Fifth Embodiment>
Next, FIG. 17 is a top sectional view showing the inside of the assembled battery 1 of the fifth embodiment. For convenience of explanation, the same parts as those in the first embodiment shown in FIGS. 1 to 9 described above are designated by the same reference numerals. The assembled battery 1 of the present embodiment includes an electrode cover 41. Other parts are the same as those in the first embodiment.

Electrode covers 41 and 42 are arranged on the front surface and the back surface of the battery array 2 in which the positive electrodes 5 and the negative electrodes 6 of the cell cells 3 project alternately. The electrode covers 41 and 42 are formed of glass epoxy or the like, and have a plurality of groove portions 41a and 42a into which each positive electrode 5 and each negative electrode 6 are inserted. Further, groove portions 41b for inserting terminals 7 and 8 to be pulled out to the outside of the outer container 10 are further provided at both ends of the electrode cover 41 arranged on the front surface of the battery array 2.

18 and 19 show a rear view of the electrode cover 41 and a front view of the electrode cover 42. A metal film conductor (not shown) in contact with the positive electrode 5 and the negative electrode 6 is arranged on the inner surfaces of the grooves 41a and 41b of the electrode cover 41. The positive electrode 5 and the negative electrode 6 are press-fitted into the groove 41a and pressed onto the inner wall of the groove 41b to come into contact with the conductor. Similarly, a metal film conductor (not shown) in contact with the positive electrode 5 and the negative electrode 6 is arranged on the inner surface of the groove 42a of the electrode cover 42. The positive electrode 5 and the negative electrode 6 are press-fitted into the groove 42a and come into contact with the conductor.

The conductor may be formed of a metal leaf spring, and the positive electrode 5 and the negative electrode 6 may be brought into contact with the conductor by the elasticity of the leaf spring.

A plurality of wiring patterns 41c are formed on the electrode cover 41. Every other conductor in the groove 41a adjacent to the X direction is electrically connected by the wiring pattern 41c. Similarly, a plurality of wiring patterns 42c are formed on the electrode cover 42. Every other conductor in the groove 42a adjacent to the X direction is electrically connected by the wiring pattern 42c. As a result, each cell 3 is connected in series, and the lead wire can be omitted, and the joining work such as soldering and welding can be omitted.

In the assembled battery 1 having the above configuration, the gap between the battery array 2 and the cylindrical portion 11 (see FIG. 2) of the outer container 10 can be reduced by the electrode cover 41. Therefore, the vacuum inside the outer container 10 can be evacuated in a short time, and the man-hours of the assembled battery 1 can be reduced. Further, it is possible to prevent the outer container 10 from being damaged due to the positive electrode 5 and the negative electrode 6 coming into contact with the outer container 10 by evacuation.

According to this embodiment, the same effect as that of the first embodiment can be obtained. Further, since the electrode cover 41 having the groove portion 41a into which the positive electrode 5 and the negative electrode 6 are inserted is provided, the man-hours of the assembled battery 1 can be reduced and the outer container 10 can be prevented from being damaged by evacuation.

Further, conductors are arranged on the inner surfaces of the groove portions 41a and 41b, and the conductors of the predetermined groove portions 41a are electrically connected by the wiring pattern 41c. Therefore, the lead wire connecting the positive electrode 5 and the negative electrode 6 can be omitted, and the cost of the assembled battery 1 can be reduced.

<Sixth Embodiment>
Next, FIG. 20 is a top sectional view showing the inside of the assembled battery 1 of the fifth embodiment. Further, FIG. 21 shows a rear view of the electrode cover 41 of the assembled battery 1. For convenience of explanation, the same parts as those in the fifth embodiment shown in FIGS. 17 and 18 described above are designated by the same reference numerals. In this embodiment, the structures of the electrode covers 41 and 42 are different from those in the fifth embodiment. Other parts are the same as those in the fifth embodiment.

The positive electrode 5 and the negative electrode 6 protruding from each cell 3 of the battery array 2 are bent in different directions in the X direction, and are arranged so that the positive electrode 5 and the negative electrode 6 adjacent to each other in the X direction come into contact with each other. As a result, the lead wire connecting the positive electrode 5 and the negative electrode 6 and the wiring pattern 41c (see FIG. 18) on the electrode cover 41 can be omitted. In addition, in order to make the contact more reliable, the positive electrode 5 and the negative electrode 6 may be joined in advance by soldering, welding, or the like.

The groove portion 41a provided in the electrode cover 41 can be integrally inserted with the positive electrode 5 and the negative electrode 6 in contact with each other. Although not shown, the groove portion 42a (see FIG. 19) provided in the electrode cover 42 can also be integrally inserted with the positive electrode 5 and the negative electrode 6 in contact with each other. Thereby, the same effect as that of the fifth embodiment can be obtained.

In the first to sixth embodiments, the tubular portion 11 of the outer container 10 is formed to have a rectangular cross section, but a polygonal cross section other than the rectangular cross section may be used. At this time, the bottom surface portion 22 of the end face sealing portion 21 is formed in a polygonal shape corresponding to the tubular portion 11.

The type of the secondary battery constituting the cell 3 of the first to sixth embodiments is not particularly limited, and for example, a lithium ion battery, a lithium ion polymer battery, a lead battery, a nickel / hydrogen battery, and nickel. -Cadmium livestock batteries, nickel / iron livestock batteries, nickel / zinc livestock batteries, silver oxide / zinc livestock batteries, metal air batteries, polyvalent cation batteries, etc. Among these secondary batteries, suitable application targets of the cell 3 of each embodiment include a lithium ion battery, a lithium ion polymer battery, a lithium ion all-solid-state battery, and the like.

Further, although the cell 3 of the first to sixth embodiments is a secondary battery, it is defined by the concept that a positive electrode and a negative electrode are included in the housing body. Therefore, for example, a capacitor and an electric double layer. It also includes power storage devices such as capacitors (EDLC) and lithium ion capacitors.

According to the present invention, it can be widely used as an assembled battery in which a battery array in which a plurality of cells are arranged side by side is sealed by an outer container.

1 set battery 2 battery array 3 cell cell 4 storage body 5 positive electrode 6 negative electrode 7, 8 terminals 10 outer container 11 tubular part 11a heat-bonded part 11c protruding part 21 end face sealing part 22 bottom part 23 side part 25 skeleton part 25a Circular part 25b Columnar part 26 Frame part 26a Flange part 26b Opening 41, 42 Electrode cover 41a, 41b, 42a Groove 41c, 42c Wiring pattern 50, 51 Resin sheet 52, 58 Thermal adhesive resin layer 54 Base material layer 56 Barrier Layer 60 Blank plate 61, 61a, 62a Folded wire 62 Bottom plate 63a, 63c Side plate 63b, 63d Reinforcing plate 64a, 64c Folded piece 65 Flap 68 Connecting piece 70 Heating tool

Claims (13)

In an assembled battery including a battery array in which a plurality of cells having positive and negative electrodes are electrically connected and arranged side by side, and an outer container for sealing and outering the battery array, the outer container is at least on the inner surface. A tubular portion formed into a cylindrical shape by a resin sheet on which a heat-adhesive resin layer is arranged, and a plurality of side surface portions are erected from each side of a polygonal bottom surface portion, and both ends in the axial direction of the tubular portion. It has a pair of end face sealing portions for sealing each surface, the bottom surface portion is formed of a resin sheet, and the side surface portion extends outward from the bottom surface portion in the axial direction to the inner surface of the tubular portion. An assembled battery characterized by being heat-bonded. The assembled battery according to claim 1, wherein a radial fold line is provided on the bottom surface portion. The set according to claim 1 or 2, wherein the outer side of the side surface portion in the axial direction is heat-bonded to the inner surface of the tubular portion, and the inner side is non-adhesive to the tubular portion. battery. The aspect according to any one of claims 1 to 3, wherein the bottom surface portion and the side surface portion are formed by bending a resin sheet, and a heat-adhesive resin layer is provided on the outer surface of the side surface portion. Assembled battery. The set according to claim 4, wherein the adjacent side surface portions are connected by a connecting piece bent from the side surface portion, and the connecting piece is folded in half by a folding line extending from a corner of the bottom surface portion. battery. The assembled battery according to any one of claims 1 to 3, wherein the bottom surface portion and the side surface portion are integrally molded products of a resin sheet. The assembled battery according to any one of claims 1 to 3, wherein the end face sealing portion is made of a cold-molded product of a resin sheet. The end face sealing portion has an annular portion and a skeleton portion composed of an integrally molded product of a plurality of columnar portions erected from the annular portion, and the bottom surface portion and the side surface portion are bent resin sheets. Any of claims 1 to 3, wherein the bottom surface portion and the inner surface of the side surface portion are adhered to the skeleton portion, and a heat-adhesive resin layer is provided on the outer surface of the side surface portion. The assembled battery described in Crab. Claims 1 to 3, wherein the side surface portion is formed by an annular frame portion of a resin molded product, and the bottom surface portion adheres to the side surface portion to close one opening surface of the frame portion. The assembled battery described in either. The assembled battery according to any one of claims 1 to 9, wherein the inside of the outer container is depressurized. The assembled battery according to claim 10, further comprising an electrode cover having a plurality of grooves into which the positive electrode and the negative electrode are inserted and arranged on the battery array. The assembled battery according to claim 11, wherein the electrode cover has a conductor arranged on the inner surface of the groove portion and a wiring pattern for electrically connecting the conductor of the predetermined groove portion. In an outer container for assembled batteries in which a plurality of cells having positive and negative electrodes are electrically connected and a battery array arranged side by side is sealed and exteriorized, the outer container is formed into a cylindrical shape by a resin sheet and is heat-bonded to at least the inner surface. A pair of end face sealing portions that have a tubular portion having a sex resin layer and a plurality of side surface portions erected from each side of a polygonal bottom surface portion and seal both end faces in the axial direction of the tubular portion. The bottom surface portion is formed of a resin sheet, and the side surface portion extends outward in the axial direction from the bottom surface portion and is thermally adhered to the inner surface of the cylindrical portion. Outer container.

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