JP6183231B2 - Terminal film for power storage device and power storage device - Google Patents

Description

  The present invention relates to a terminal film for an electricity storage device and an electricity storage device, in particular, a packaging material for packaging an electricity storage device body, a metal terminal that is electrically connected to the electricity storage device body and extends outside the packaging material, The present invention relates to a terminal film for an electricity storage device and an electricity storage device interposed therebetween.

  In recent years, there has been an increasing demand for miniaturization of portable devices and effective use of natural energy, and research and development of lithium-ion secondary batteries (one of storage devices) with higher voltage and higher energy density has been conducted. It has been broken.

  As a packaging material used for the lithium ion secondary battery, metal cans have been used in the past, but because of the low manufacturing cost in response to demands for thinner and diversified products to be applied, A packaging material in which a laminated body obtained by laminating a metal layer (for example, an aluminum foil) and a resin film is formed into a bag shape is often used.

  The lithium ion secondary battery includes a battery body, a packaging material that wraps the battery body, a metal terminal (tab lead) that is connected to the negative electrode or the positive electrode of the battery body, and extends to the outside of the packaging material. And a terminal film for an electricity storage device (also referred to as “tab sealant”) covering each of the outer peripheral side surfaces.

Examples of the structure of the terminal film for an electricity storage device include a single layer structure and a laminated structure (for example, see Patent Document 1).
Patent Document 1 discloses a terminal film for an electricity storage device (lead wire film) in which polypropylene graft-deformed with an unsaturated carboxylic acid or polyethylene graft-deformed with an unsaturated carboxylic acid is laminated in three layers.

The terminal film for electricity storage device includes, for example, an extrusion method using a round die such as an inflation molding method, a push die method using a T die, and the like, and a film extrusion manufacturing apparatus having a die such as a round die or a T die It is manufactured using.
A terminal film for an electricity storage device manufactured by such an apparatus (specifically, a film extrusion manufacturing apparatus or the like) is wound around a winding roller constituting the apparatus, and is transported and stored. And when using (processing) the terminal film for electrical storage devices made into the roll shape, it processes while pulling out one end of the terminal film for electrical storage devices made into the roll shape.

JP 2003-123710 A

  However, when the manufactured power storage device terminal film is wound up in a roll shape, both surfaces (a pair of outer surfaces) of the power storage device terminal film are flat surfaces, so that the contact between the power storage device terminal films in contact with each other An area will become large and the adhesiveness between the terminal films for electrical storage devices will improve.

  For this reason, when it processed while pulling out one end of the terminal film for electrical storage devices made into the roll shape, there existed a problem that the blocking phenomenon generate | occur | produced between the terminal films for electrical storage devices to contact.

  Accordingly, an object of the present invention is to provide an electricity storage device terminal film and an electricity storage device capable of suppressing the occurrence of a blocking phenomenon when one end of the rolled electricity storage device terminal film is pulled out. And

  In order to solve the above problems, the terminal film for an electricity storage device according to one embodiment of the present invention is disposed so as to cover a part of the outer peripheral surface of the metal terminal that is electrically connected to the electricity storage device body constituting the electricity storage device. The first outermost layer including the first insulating layer, the second outermost layer including the second insulating layer, and the first and second insulating layers, And an amorphous insulating filler added to at least one of the insulating layers, wherein a part of the amorphous insulating filler protrudes from the outer surface of the insulating layer.

  According to the present invention, a part of the amorphous insulating filler added to at least one of the first and second insulating layers is disposed so as to protrude from the outer surface of the insulating layer. By reducing the contact area between the terminal films for electricity storage devices when the terminal films for devices are brought into contact with each other, it is possible to improve the slipping property between the terminal films for electricity storage devices (in other words, to improve the anti-blocking effect). It becomes possible.

  Thereby, it can suppress that a blocking phenomenon generate | occur | produces, for example when pulling out the end of the terminal film for electrical storage devices wound up by roll shape.

  Furthermore, when the insulating layer includes an insulating filler, the insulating filler functions as a spacer when the power storage device terminal film is fused to the metal terminal. For this reason, since it becomes possible to suppress that the thickness of an insulating layer becomes thin, the insulation of the outermost layer which consists of an insulating layer containing an amorphous insulating filler can be improved.

  Moreover, the terminal film for electrical storage devices which concerns on 1 aspect of the said invention WHEREIN: The range of 0.1-20 micrometers may be sufficient as the average particle diameter of the said amorphous insulating filler.

If the average particle size of the amorphous insulating filler is smaller than 0.1 μm, the size of the amorphous insulating filler protruding from the outer surface of the insulating layer becomes too small, and it is difficult to obtain a sufficient anti-blocking effect. turn into.
On the other hand, if the average particle size of the amorphous insulating filler is larger than 20 μm, the size of the amorphous insulating filler is too large, so that the contact area with the metal terminal (in other words, tab lead) or the packaging material is small. As a result, the adhesiveness is lowered.
Therefore, by setting the average particle size of the amorphous insulating filler in the range of 0.1 to 20 μm, a sufficient antiblocking effect can be obtained and the adhesion can be improved.

  Further, in the terminal film for an electricity storage device according to one embodiment of the present invention, the thickness of the insulating layer to which the amorphous insulating filler is added is 2 to 2 of the average particle diameter of the amorphous insulating filler. The value may be 30 times.

When the thickness of the insulating layer to which the amorphous insulating filler is added is smaller than twice the average particle size of the amorphous insulating filler, the amorphous insulating filler protruding from the outer surface of the insulating layer Therefore, the adhesion with the metal terminal (in other words, tab lead) and the packaging material is lowered.
When the thickness of the insulating layer to which the amorphous insulating filler is added is larger than 30 times the average particle size of the amorphous insulating filler, the ratio of the amorphous insulating filler protruding from the insulating layer Is extremely low, it becomes difficult to obtain a sufficient anti-blocking effect.
Therefore, a sufficient anti-blocking effect can be obtained by setting the thickness of the insulating layer to which the amorphous insulating filler is added to a value 2 to 30 times the average particle size of the amorphous insulating filler. In addition, the adhesion can be improved.

  Moreover, the terminal film for electrical storage devices which concerns on 1 aspect of the said invention WHEREIN: 0.1-20 wt% may be added of the said amorphous insulating filler.

If the amount of amorphous insulating filler added is less than 0.1%, the number of amorphous insulating fillers protruding from the outer surface of the insulating layer is too small, so the contact area between terminal films for power storage devices is reduced. Effect is insufficient.
Thereby, it becomes difficult to improve the slipperiness (in other words, to improve the anti-blocking effect) between the terminal films for power storage devices in contact.

On the other hand, if the amount of the amorphous insulating filler added is more than 20%, the number of amorphous insulating fillers protruding from the outer surface of the insulating layer becomes too large. Will reduce the contact area between the insulating layers.
Thereby, it becomes difficult to ensure sufficient adhesion between the terminal film for electricity storage device and the metal terminal or packaging material after fusion bonding of the terminal film for electricity storage device and the metal terminal or packaging material.

  Therefore, the adhesiveness between the terminal film for electrical storage devices and the metal terminal or the packaging material is lowered by setting the amount of the amorphous insulating filler contained in the insulating layer to 0.1 to 20%. Without this, it is possible to improve the slipping property (in other words, to improve the anti-blocking effect) between the terminal films for power storage devices that come into contact.

  In the terminal film for an electricity storage device according to one embodiment of the present invention, the amorphous filler may be added to only one of the first and second insulating layers.

  Thus, even when an amorphous filler is added to only one of the first and second insulating layers, the slipping property between the terminal films for power storage devices in contact is improved (in other words, the anti-blocking effect) Can be improved).

  Thereby, it can suppress that a blocking phenomenon generate | occur | produces, for example when pulling out the end of the terminal film for electrical storage devices wound up by roll shape.

  Furthermore, since the insulating filler functions as a spacer, it is possible to suppress the thickness of the insulating layer from being reduced, so that it is possible to improve the insulation of the outermost layer made of an insulating layer containing an amorphous insulating filler. it can.

  Further, in the terminal film for an electricity storage device according to one embodiment of the present invention, a third insulating layer disposed between the first outermost layer and the second outermost layer, and the third insulating layer You may have an intermediate | middle layer containing the pigment added to.

In this way, the intermediate layer includes the third insulating layer disposed between the first outermost layer and the second outermost layer, and the intermediate layer containing the pigment added to the third insulating layer. Can be colored with a pigment.
Thereby, since the visibility of the terminal film for electrical storage devices is improved, the determination as to whether or not the electrical storage device terminal film is attached to the metal terminal and the determination of the attachment position of the electrical storage device terminal film with respect to the metal terminal are accurately performed. be able to.

  Further, in the terminal film for an electricity storage device according to one aspect of the present invention, a fourth film is provided between the intermediate layer and the first outermost layer and between the intermediate layer and the second outermost layer. An insulating layer may be provided.

  Thus, by arranging the fourth insulating layer between the intermediate layer and the first outermost layer and between the intermediate layer and the second outermost layer, for example, the pigment has conductivity. In the case of using carbon black, the insulation between the intermediate layer and the metal layer constituting the packaging material and the insulation between the intermediate layer and the metal terminal can be further improved.

  In order to solve the above-described problem, an electricity storage device according to one embodiment of the present invention is the electricity storage device terminal film according to any one of claims 1 to 7, an electricity storage device body to be charged and discharged, and the electricity storage device. A pair of the metal terminals that are electrically connected to the main body and partially covered with the power storage device terminal film; a part of the power storage device terminal film; and a packaging material that covers the power storage device main body. It is characterized by that.

  According to this invention, while the terminal film for electrical storage devices of any one of Claims 1 thru | or 7 covers a part of metal terminal, while being able to acquire sufficient anti-blocking effect, a metal terminal Adhesiveness can be improved.

  Further, in the electricity storage device according to one aspect of the present invention, of the first and second outermost layers, one outermost layer is disposed so as to cover a part of the outer peripheral surface of the metal terminal, and the other outermost layer is disposed. You may arrange | position an outermost layer so that the said packaging material may be contacted.

  Thus, the adhesiveness with a packaging material can be improved by arrange | positioning the other outermost layer so that it may contact with a packaging material.

  According to the electricity storage device terminal film and the electricity storage device of the present invention, it is possible to suppress the occurrence of a blocking phenomenon when one end of the rolled electricity storage device terminal film is pulled out.

It is a perspective view which shows schematic structure of the electrical storage device which concerns on embodiment of this invention. It is sectional drawing which shows an example of the cut surface of the packaging material shown in FIG. It is sectional drawing of the AA line direction of the terminal film for electrical storage devices shown in FIG. 1, and a metal terminal. It is typical sectional drawing which expanded a part of terminal film for electrical storage devices wound by roll shape.

  Embodiments to which the present invention is applied will be described below in detail with reference to the drawings. The drawings used in the following description are for explaining the configuration of the embodiment of the present invention. The size, thickness, dimensions, and the like of each part shown in the drawings are the actual terminal film for an electricity storage device and the electricity storage device. It may be different from the dimensional relationship.

(Embodiment)
FIG. 1 is a perspective view showing a schematic configuration of an electricity storage device according to an embodiment of the present invention. In FIG. 1, as an example of the electricity storage device 10, a lithium ion secondary battery is illustrated as an example, and the following description is given.
Note that the lithium ion secondary battery configured as shown in FIG. 1 is sometimes called a battery pack or a battery cell.

  Referring to FIG. 1, an electricity storage device 10 according to the present embodiment is a lithium ion secondary battery, and may be called an electricity storage device body 11, a packaging material 13, and a pair of metal terminals 14 (“tab leads”). ) And a terminal film 16 for an electricity storage device (sometimes referred to as “tab sealant”).

  The power storage device body 11 is a battery body that performs charging and discharging. The packaging material 13 is disposed so as to cover the surface of the electricity storage device body 11 and to be in contact with a part of the electricity storage device terminal film 16.

  2 is a cross-sectional view showing an example of a cut surface of the packaging material shown in FIG. 2, the same components as those in the structure shown in FIG.

Here, an example of the configuration of the packaging material 13 will be described with reference to FIG.
The packaging material 13 includes an inner layer 21, an inner-side adhesive layer 22, a corrosion prevention treatment layer 23-1, a barrier layer 24 that is a metal layer, and a corrosion prevention treatment layer 23 from the inside contacting the power storage device body 11. -2, outer layer side adhesive layer 25, and outer layer 26 are sequentially laminated.

As a base material of the inner layer 21, for example, an acid-modified polyolefin resin obtained by graft-modifying maleic anhydride or the like on a polyolefin resin or a polyolefin resin can be used.
Examples of the polyolefin resin include low density, medium density, and high density polyethylene; ethylene-α olefin copolymer; homo, block, or random polypropylene; propylene-α olefin copolymer. These polyolefin resins may be used individually by 1 type, and may use 2 or more types together.

Further, the inner layer 21 may be configured by using a single layer film or a multilayer film in which a plurality of layers are laminated according to a required function. Specifically, for example, in order to impart moisture resistance, a multilayer film in which a resin such as an ethylene-cyclic olefin copolymer or polymethylpentene is interposed may be used.
Furthermore, the inner layer 21 may contain various additives (for example, a flame retardant, a slip agent, an antiblocking agent, an antioxidant, a light stabilizer, a tackifier, etc.), for example.

The thickness of the inner layer 21 is preferably set within a range of 10 to 150 μm, for example, but more preferably 30 to 80 μm.
If the thickness of the inner layer 21 is less than 10 μm, the heat seal adhesion between the packaging materials 13 and the adhesion with the terminal film 16 for an electricity storage device may be reduced. Moreover, since it will become a factor of the cost increase of the packaging material 13 when the thickness of the inner layer 21 is thicker than 150 micrometers, it is unpreferable.

As the inner layer side adhesive layer 22, for example, a known adhesive such as a general dry lamination adhesive or an acid-modified heat-fusible resin can be appropriately selected and used.
As shown in FIG. 2, the corrosion prevention treatment layers 23-1 and 23-2 are preferably formed on both surfaces of the barrier layer 24 in terms of performance. However, considering the cost, the inner side adhesive layer 22 side is provided. You may arrange | position the corrosion prevention process layer 23-1 only to the surface of the barrier layer 24 located.

The barrier layer 24 is a conductive metal layer. Examples of the material of the barrier layer 24 include aluminum and stainless steel, but aluminum is preferable from the viewpoint of cost, weight (density), and the like.
As the outer layer side adhesive layer 25, for example, a polyurethane-based general adhesive mainly composed of polyester polyol, polyether polyol, acrylic polyol or the like can be used.

As the outer layer 26, for example, a single film such as nylon or polyethylene terephthalate (PET), or a multilayer film can be used.
The outer layer 26 may contain, for example, various additives (for example, a flame retardant, a slip agent, an antiblocking agent, an antioxidant, a light stabilizer, a tackifier, and the like) like the inner layer 21.
Further, the outer layer 26 may have a protective layer formed by laminating a resin insoluble in the electrolytic solution or coating a resin component insoluble in the electrolytic solution as a countermeasure against liquid leakage, for example. .

  FIG. 3 is a cross-sectional view of the electricity storage device terminal film and metal terminal shown in FIG. In FIG. 3, the same components as those in the structure shown in FIG.

Referring to FIGS. 1 and 3, the pair (two in FIG. 1) of metal terminals 14 includes a metal terminal body 14-1 and a corrosion prevention layer 14-2.
Of the pair of metal terminal bodies 14-1, one metal terminal body 41-1 is electrically connected to the positive electrode of the electricity storage device body 11, and the other metal terminal body 41-1 is electrically connected to the electricity storage device body 11. Is electrically connected to the negative electrode.
The pair of metal terminal bodies 14-1 extends in a direction away from the electricity storage device body 11, and part of the metal terminal bodies 14-1 is exposed from the packaging material 13. The shape of the pair of metal terminal bodies 14-1 can be, for example, a flat plate shape.

  A metal can be used as the material of the metal terminal body 14-1. The metal used as the material of the metal terminal body 14-1 is preferably determined in consideration of the structure of the electricity storage device body 11, the material of each component of the electricity storage device body 11, and the like.

For example, when the electricity storage device 10 is a lithium ion secondary battery, aluminum is used as the positive electrode current collector, and copper is used as the negative electrode current collector.
In this case, it is preferable to use aluminum as the material of the metal terminal body 14-1 connected to the positive electrode of the electricity storage device body 11. In consideration of corrosion resistance to the electrolyte, it is preferable to use, for example, an aluminum material having a purity of 97% or more such as 1N30 as the material of the metal terminal body 14-1 connected to the positive electrode of the electricity storage device body 11. is there.

Furthermore, when bending the metal terminal body 14-1, it is preferable to use an O material tempered by sufficient annealing for the purpose of adding flexibility.
As a material of the metal terminal body 14-1 connected to the negative electrode of the electricity storage device body 11, it is preferable to use copper having a nickel plating layer formed on the surface or nickel.

The thickness of the metal terminal body 14-1 depends on the size and capacity of the lithium ion secondary battery. When the lithium ion secondary battery is small, the thickness of the metal terminal body 14-1 is preferably 50 μm or more, for example.
Moreover, in the case of a large-sized lithium ion secondary battery for power storage and in-vehicle use, the thickness of the metal terminal body 14-1 can be set as appropriate within a range of 100 to 500 μm, for example.

The corrosion prevention layer 14-2 is disposed so as to cover the surface of the metal terminal body 14-1. In the case of a lithium ion secondary battery, a corrosive component such as LiPF ₆ is included in the electrolytic solution.
The corrosion prevention layer 14-2 is a layer for suppressing the metal terminal body 14-1 from being corroded by a corrosive component such as LiPF ₆ contained in the electrolytic solution.

  Referring to FIG. 3, the power storage device terminal film 16 is disposed so as to cover a part of the outer peripheral surface of the metal terminal 14. The power storage device terminal film 16 includes a first outermost layer 31 that contacts the outer peripheral side surface of the metal terminal 14, a second outermost layer 32 that contacts the packaging material 13, a first outermost layer 31, and a second outermost layer. The intermediate layer 33 disposed between the outer layer 32 and the outer layer 32 is laminated.

The first outermost layer 31 is disposed so as to cover one surface of the intermediate layer 33 including the pigment 42. The first outermost layer 31 is configured to include a first insulating layer 35 that is an insulating resin layer, and an amorphous insulating filler 36 (an insulating filler having an irregular shape).
The first insulating layer 35 (in other words, the first outermost layer 31) is disposed so as to cover a part of the outer peripheral surface of the metal terminal 14.
The first outermost layer 31 is disposed so as to cover the outer peripheral surface of the metal terminal 14, thereby sealing the circumferential direction of the metal terminal 14 and bringing the power storage device terminal film 16 and the metal terminal 14 into close contact with each other. It has a function.

  Therefore, as a material constituting the first insulating layer 35, for example, a resin having excellent adhesiveness may be used. As the resin material constituting the first insulating layer 35, for example, an acid-modified polyolefin resin obtained by graft-modifying maleic anhydride or the like on a polyolefin resin can be used.

The second outermost layer 32 is disposed so as to cover the other surface of the intermediate layer 33 including the pigment 42. The second outermost layer 32 includes a second insulating layer 38 that is an insulating resin layer and an amorphous insulating filler 36 (an insulating filler having an irregular shape).
The second insulating layer 38 (in other words, the second outermost layer 32) is brought into contact with the packaging material 13 by being fused with the packaging material 13 (specifically, the inner layer 21 shown in FIG. 2). Yes.

The first insulating layer 35 is fused to the packaging material 13 to seal the inside of the packaging material 13, and the storage device terminal film 16 and the packaging material 13 (specifically, the inner layer shown in FIG. 2). 21).
Therefore, from the viewpoint of adhesion to the packaging material 13, it is preferable to use a resin (for example, polyolefin resin) of the same system as the resin that becomes the base material of the inner layer 21 as the first insulating layer 35.

  The thickness of the 1st insulating layer 35 is good to set it as the value 2-30 times the average particle diameter (for example, 0.1-20 micrometers) of the amorphous insulating filler 36, for example.

When the thickness of the first insulating layer 35 to which the amorphous insulating filler 36 is added is smaller than twice the average particle size of the amorphous insulating filler 36, the outer surface 35a of the first insulating layer 35 is obtained. Since the ratio of the insulative insulating filler 36 protruding from the surface becomes too large, the adhesion with the metal terminal 14 (in other words, the tab lead) is lowered.
When the thickness of the first insulating layer 35 to which the amorphous insulating filler 36 is added is larger than 30 times the average particle size of the amorphous insulating filler 36, the outer surface 35a of the first insulating layer 35 is obtained. Since the ratio of the amorphous insulating filler 36 protruding from the region becomes extremely low, it becomes difficult to obtain a sufficient anti-blocking effect.
Therefore, a sufficient anti-blocking effect can be obtained by setting the thickness of the first insulating layer 35 to which the amorphous insulating filler 36 is added to a value 2 to 30 times the average particle diameter of the amorphous insulating filler 36. Can be obtained, and adhesion can be improved.

  FIG. 4 is a schematic cross-sectional view in which a part of the terminal film for an electricity storage device wound in a roll shape is enlarged. In FIG. 4, the same components as those of the structure shown in FIG.

  Referring to FIGS. 3 and 4, the amorphous insulating filler 36 is added to the first insulating layer 35. The amorphous insulating filler 36 is arranged so that a part thereof protrudes from the outer surface 35a of the first insulating layer 35 (surface that contacts the corrosion prevention layer 14-2 shown in FIG. 3). The part which protruded from the outer surface 35a among the amorphous insulating fillers 36 functions as an antiblocking agent.

Thus, by arranging a part of the amorphous insulating filler 36 so as to protrude from the outer surface 35a of the first insulating layer 35, for example, as shown in FIG. In this case, the outer surface 35a located around the amorphous insulating filler 36 protruding from the outer surface 35a does not come into contact with the outer surface 38a of the second insulating layer 38. Specifically, the contact area between the outer surface 35a of the first insulating layer 35 and the outer surface 38a of the second insulating layer 38 can be reduced. Thereby, it becomes possible to improve the slipping property between the terminal films 16 for electrical storage devices which contact (in other words, the antiblocking effect is improved).
Therefore, it can suppress that a blocking phenomenon generate | occur | produces when pulling out the end of the terminal film 16 for electrical storage devices wound by roll shape.

The insulative insulating filler 36 is subjected to a fusion process (after a process of applying a predetermined temperature and pressure to melt-bond the packaging material 13 and the second outermost layer 32), and then to the first outermost layer 31. It also functions as a spacer for securing the thickness.
For this reason, since it becomes possible to suppress that the thickness of the 1st outermost layer 31 becomes thinner than predetermined thickness after a melt | fusion process, for example, electroconductive carbon black is used as the pigment 42 which comprises the intermediate | middle layer 33. Even when used, the electrical insulation between the metal terminal 14 and the intermediate layer 33 can be sufficiently ensured.

The amorphous insulating filler 36 may be an amorphous transparent insulating filler or a colored amorphous insulating filler. Specifically, as the amorphous insulating filler 36, for example, a filler made of a metal oxide (for example, alumina or silica), a filler made of an organic material (for example, polycarbonate or epoxy resin), or the like can be used. .
From the viewpoint of the cost of the terminal film 16 for an electricity storage device, the amorphous insulating filler 36 is preferably an inexpensive amorphous silica filler.

The average particle diameter of the amorphous insulating filler 36 is preferably in the range of 0.1 to 20 μm, for example.
If the average particle size of the amorphous insulating filler 36 is smaller than 0.1 μm, the size of the amorphous insulating filler 36 that protrudes from the outer surface 35a of the first insulating layer 35 becomes too small. It becomes difficult to obtain.
On the other hand, if the average particle size of the amorphous insulating filler 36 is larger than 20 μm, the size of the amorphous insulating filler 36 is too large, so that the contact area with the metal terminal 14 (in other words, tab lead) is reduced. Adhesiveness will decrease.
Therefore, by setting the average particle size of the amorphous insulating filler 36 within the range of 0.1 to 20 μm, a sufficient anti-blocking effect can be obtained and the adhesion can be improved.

The addition amount of the amorphous insulating filler 36 added to the first insulating layer 35 can be appropriately set within a range of 0.1 to 20 wt%, for example.
If the amount of the amorphous insulating filler 36 added is less than 0.1 wt%, the number of the amorphous insulating fillers 36 protruding from the outer surface 35a of the first insulating layer 35 is too small. The effect of reducing the contact area between them becomes insufficient.
Thereby, it becomes difficult to improve the slipperiness (in other words, to improve the anti-blocking effect) between the terminal films 16 for power storage devices in contact.

On the other hand, when the amount of the amorphous insulating filler 36 added is more than 20 wt%, the number of the amorphous insulating fillers 36 protruding from the outer surface 35a of the first insulating layer 35 becomes too large. The contact area between the layers (specifically, the insulating layers) is considerably reduced.
This makes it difficult to ensure sufficient adhesion between the storage device terminal film 16 and the metal terminal 14 after the storage device terminal film 16 and the metal terminal 14 are fused (see FIG. 1). ).

  Accordingly, the amount of the amorphous insulating filler 36 added to the first insulating layer 35 is set in the range of 0.1 to 20 wt%, whereby the power storage device terminal film 16 and the metal terminal 14 or the packaging material 13. Can be improved (in other words, the anti-blocking effect can be improved) without reducing the adhesion between the terminal film 16 and the terminal film 16 for an electricity storage device.

3 and 4, the second outermost layer 32 is disposed so as to cover the other surface of the intermediate layer 33 including the pigment 42. The second outermost layer 32 is configured to include a second insulating layer 38 that is an insulating resin layer, and an amorphous insulating filler 39 (an insulating filler having an irregular shape).
The second insulating layer 38 (in other words, the second outermost layer 32) is brought into contact with the packaging material 13 by being fused with the packaging material 13 (specifically, the inner layer 21 shown in FIG. 2). Yes.

The second insulating layer 38 is fused to the packaging material 13 to seal the inside of the packaging material 13, and the storage device terminal film 16 and the packaging material 13 (specifically, the inner layer shown in FIG. 2). 21).
Therefore, from the viewpoint of adhesion to the packaging material 13, it is preferable to use a resin (for example, polyolefin resin) of the same system as the resin that is the base material of the inner layer 21 as the second insulating layer 38.

  The amorphous insulating filler 39 is added to the second insulating layer 38. The amorphous insulating filler 39 is arranged so that a part thereof protrudes from the outer surface 38 a of the second insulating layer 38. The part which protruded from the outer surface 38a among the amorphous insulating fillers 39 functions as an antiblocking agent.

Thereby, the amorphous insulating filler 39 arranged so that a part protrudes from the outer surface 38a of the second insulating layer 38 is arranged so that a part protrudes from the outer surface 35a of the first insulating layer 35. The same effect as that of the amorphous insulating filler 36 (specifically, the effect of improving the slipping property (in other words, improving the anti-blocking effect) between the terminal films 16 for power storage devices in contact) can be obtained. .
Therefore, it can suppress that a blocking phenomenon generate | occur | produces when pulling out the end of the terminal film 16 for electrical storage devices wound up by roll shape.

The amorphous insulating filler 39 has a thickness of the second outermost layer 32 after the fusion process (after the process of applying a predetermined temperature and pressure to bond the packaging material 13 and the second outermost layer 32). It also functions as a spacer to ensure the thickness.
For this reason, since it becomes possible to suppress that the thickness of the 2nd outermost layer 32 becomes thinner than predetermined thickness after a melt | fusion process, for example, electroconductive carbon black is used as the pigment 42 which comprises the intermediate | middle layer 33. Even when used, the electrical insulation between the barrier layer 24 (metal layer) constituting the packaging material 13 and the intermediate layer 33 can be sufficiently ensured.

The amorphous insulating filler 39 may be an amorphous transparent insulating filler or a colored amorphous insulating filler. Specifically, as the amorphous insulating filler 39, for example, a filler made of a metal oxide (for example, alumina or silica), a filler made of an organic material (for example, polycarbonate or epoxy resin), or the like can be used. .
From the viewpoint of the cost of the terminal film 16 for an electricity storage device, the amorphous insulating filler 39 is preferably an inexpensive amorphous silica filler.

If the average particle size of the amorphous insulating filler 39 is smaller than 0.1 μm, the size of the amorphous insulating filler 39 that protrudes from the outer surface 38a of the second insulating layer 38 becomes too small. It becomes difficult to obtain.
On the other hand, when the average particle diameter of the amorphous insulating filler 39 is larger than 20 μm, the size of the amorphous insulating filler 39 is too large, so that the contact area with the packaging material 13 is reduced and the adhesiveness is lowered. End up.
Therefore, by setting the average particle size of the amorphous insulating filler 39 within the range of 0.1 to 20 μm, a sufficient anti-blocking effect can be obtained and the adhesion can be improved.

The addition amount of the amorphous insulating filler 39 contained in the second insulating layer 38 can be appropriately set within a range of 0.1 to 20 wt%, for example.
When the addition amount of the amorphous insulating filler 39 contained in the second insulating layer 38 is less than 0.1 wt%, the number of the amorphous insulating filler 39 protruding from the outer surface 38a of the second insulating layer 38 is small. Therefore, the effect of reducing the contact area between the power storage device terminal films 16 is insufficient.
Thereby, it becomes difficult to improve the slipperiness (in other words, to improve the anti-blocking effect) between the terminal films 16 for power storage devices in contact.

On the other hand, if the amount of the amorphous insulating filler 39 included in the second insulating layer 38 is more than 20 wt%, the number of the amorphous insulating fillers 39 protruding from the outer surface 38a of the second insulating layer 38 is large. Therefore, the contact area between the terminal films for power storage devices (specifically, the insulating layer) is considerably reduced.
Thereby, it is difficult to sufficiently secure the adhesion between the storage device terminal film 16 and the packaging material 13 after the fusion of the storage device terminal film 16 and the packaging material 13 (after heat sealing). (See FIG. 1).

  Therefore, the amount of the amorphous insulating filler 39 contained in the second insulating layer 38 is set within the range of 0.1 to 20 wt%, so that the electricity storage device terminal film 16 and the metal terminal 14 or the packaging material 13 are added. Can be improved (in other words, the anti-blocking effect can be improved) without reducing the adhesion between the terminal film 16 and the terminal film 16 for an electricity storage device.

  The average particle size Ra of the amorphous insulating filler 39 may be the same value as or different from the average particle size Ra of the amorphous insulating filler 36 depending on the purpose.

The intermediate layer 33 is disposed between the first outermost layer 31 and the second outermost layer 32. The intermediate layer 33 has one surface covered with the first outermost layer 31 and the other surface covered with the second outermost layer 32.
The intermediate layer 33 includes a third insulating layer 41 that is an insulating resin layer disposed between the first outermost layer 31 and the second outermost layer 32, and a pigment 42 added to the third insulating layer 41. (Colorant).

As a material of the third insulating layer 41, it is preferable to use a resin material having a high melting point that is difficult to melt at the time of fusion bonding and heat sheet processing. Specifically, as the material of the third insulating layer 41, for example, polyolefin may be used from the viewpoint of adhesion to the first and second outermost layers 31 and 32.
Further, when it is desired to improve the insulation of the intermediate layer 33, the material of the third insulating layer 41 may be, for example, polyester such as PET (Polyethylene terephthalate) or a heat resistant resin (for example, polycarbonate). Good.

The third insulating layer 41 constituting the intermediate layer 33 does not need to have a single layer structure, and may have a multilayer structure in which a plurality of polyester layers are bonded together with an adhesive, for example.
The thickness of the intermediate layer 33 (in other words, the thickness of the third insulating layer 41) can be appropriately set within a range of 10 to 200 μm, for example, and preferably 20 to 100 μm.
In the intermediate layer 33, the balance between the metal terminal 14 and the first outermost layer 31 is important, and when the first outermost layer 31 and the metal terminal 14 are thick, the thickness of the intermediate layer 33 is also increased. The thickness may be increased accordingly.

The pigment 42 is for coloring the intermediate layer 33. Thus, by coloring the intermediate layer 33, it is possible to improve the visibility of the terminal film 16 for an electricity storage device as compared with the terminal film for an electricity storage device having an intermediate layer to which the pigment 42 is not added. Become.
Thereby, the inspection of the terminal film 16 for the electricity storage device (specifically, for example, the inspection whether or not the terminal film 16 for the electricity storage device is attached to the metal terminal 14, the attachment of the terminal film 16 for the electricity storage device to the metal terminal 14) The accuracy of position inspection, etc.) can be improved.

As the pigment 42, for example, an organic pigment, an inorganic pigment, or the like can be used.
Examples of organic pigments include azo, phthalocyanine, quinacridone, anthraquinone, dioxazine, indigothioindigo, perinone-perylene, and isoindolenin, and inorganic pigments include carbon black. In addition, titanium oxide-based, cadmium-based, lead-based, oxide-based flume, and the like can be used. In addition, mica (mica) fine powder, fish scale foil, and the like can be used.

As specific examples of the organic pigment, for example, the following pigments can be used.
Examples of organic pigments that can be colored yellow include isoindolinone, isoindoline, quinophthalone, anthraquinone (flavavatron), azomethine, xanthene, and the like.
Examples of organic pigments that can be colored orange include diketopyrrolopyrrole, perylene, anthraquinone, perinone, quinacridone, and the like.
Examples of organic pigments that can be colored red include anthraquinone, quinacridone, diketopyrrolopyrrole, perylene, and indigoid.

Examples of organic pigments that can be colored purple include oxazine (dioxazine), quinacridone, perylene, indigoid, anthraquinone, xanthene, benzimidazolone, violanthrone, and the like.
As an organic pigment that can be colored blue, for example, phthalocyanine, anthraquinone, indigoid and the like can be used.
Examples of organic pigments that can be colored green include phthalocyanine, perylene, azomethine, and the like.

As specific examples of the inorganic pigment, for example, the following pigments can be used.
Examples of inorganic pigments that can be colored white include zinc white, lead white, lithopone, titanium dioxide, precipitated barium sulfate, barite powder, and the like.
Examples of inorganic pigments that can be colored red include red lead, iron oxide red, and the like.
As an inorganic pigment that can be colored yellow, for example, yellow lead, zinc yellow (zinc yellow 1 type, zinc yellow 2 type) and the like can be used.
As an inorganic pigment that can be colored blue, for example, ultramarine blue, prussian blue (potassium ferrocyanide), or the like can be used.
As the inorganic pigment that can be colored black, for example, carbon black or the like can be used.

  Content of the said organic pigment and inorganic pigment contained in the 3rd insulating layer 41 can be suitably set within the range of 0.01 wt% or more and 3.00 wt% or less.

As the pigment 42, for example, carbon black is preferably used.
In this manner, by adding carbon black to the third insulating layer 41, the intermediate layer 33 can be colored with a deep hue (specifically, black).

As a result, the visibility of the electricity storage device terminal film 16 is further improved, so that the inspection of the electricity storage device terminal film 16 (specifically, for example, whether the electricity storage device terminal film 16 is attached to the metal terminal 14 or not). And the inspection of the mounting position of the storage device terminal film 16 with respect to the metal terminal 14) can be performed with higher accuracy.
In particular, it is effective when the width of the metal terminal 14 is narrow and the width of the terminal film 16 for an electricity storage device is narrow.

The particle size of the carbon black used as the pigment 42 can be appropriately selected within a range of 1 nm to 1 μm, for example.
The amount of carbon black added to the third insulating layer 41 is preferably 0.01 wt% or more and 3.00 wt% or less, for example.
If the added amount of carbon black contained in the third insulating layer 41 is less than 0.01 wt% or more, it becomes difficult to color the intermediate layer 33 with a deep hue. In addition, if the content of carbon black contained in the third insulating layer 41 is more than 3.00 wt%, the conductivity of the intermediate layer 33 becomes too high, so that the electricity between the intermediate layer 33 and the metal terminal 14 is increased. It is difficult to ensure sufficient insulation.

  Therefore, by making the addition amount of carbon black contained in the third insulating layer 41 not less than 0.01 wt% and not more than 3.00 wt%, the visibility of the terminal film 16 for an electricity storage device can be improved and electrical insulation can be achieved. Sufficient sex can be secured.

Note that an insulating filler (not shown) may be added to the third insulating layer 41. That is, the intermediate layer 33 may include the insulating filler (not shown) as a component.
Thus, by adding an insulating filler (not shown) to the third insulating layer 41, the insulating filler functions as a spacer. Therefore, after fusion, the intermediate layer 33 (specifically, It can be suppressed that the thickness of the third insulating layer 41) becomes thinner than a predetermined thickness.

As the insulating filler, for example, a filler made of a metal oxide (for example, alumina or silica), a filler made of an organic material (for example, polycarbonate or epoxy resin), or the like can be used. From the viewpoint of the cost of the terminal film 16 for an electricity storage device, a silica filler is preferable as the insulating filler.
As the shape of the insulating filler, for example, a spherical shape or an indefinite shape can be used.

According to the terminal film for an electricity storage device of the present embodiment, the amorphous insulating filler 36 added to the first insulating layer 35 is disposed so as to protrude from the outer surface 35a of the first insulating layer 35, and the first The amorphous insulating filler 39 added to the second insulating layer 38 is disposed so as to protrude from the outer surface 38a of the second insulating layer 38, so that the power storage device terminal film 16 is brought into contact therewith. It is possible to reduce the contact area between the terminal films 16 and improve the slipping property (in other words, improve the anti-blocking effect) between the terminal films 16 for power storage devices in contact.
Thereby, it can suppress that a blocking phenomenon generate | occur | produces when pulling out the end of the terminal film 16 for electrical storage devices wound up by roll shape, for example.

Moreover, when the 1st and 2nd insulating layers 35 and 38 contain the insulating fillers 36 and 39, when the electrical storage device terminal film 16 is fused to the metal terminals 14, the amorphous insulating fillers 36 and 39 are formed. Functions as a spacer.
As a result, it is possible to prevent the first and second insulating layers 35 and 38 from becoming thinner than a predetermined thickness, and thus the first and second outermost layers including the amorphous insulating fillers 36 and 39 are included. The insulating properties of the outer layers 31 and 32 can be improved.

  Therefore, for example, even when carbon black having conductivity (a pigment having excellent visibility) is added as the pigment 42 to the third insulating layer 41, the first and second outermost layers 31 and 32 provide conductivity. The intermediate layer 33 having the metal terminal 14 and the barrier layer 24 can be electrically insulated.

  Moreover, the electrical storage device 10 of the present embodiment having the electrical storage device terminal film 16 can obtain the same effects as the electrical storage device terminal film 16.

  In the present embodiment, the amorphous insulating fillers 36 and 39 are added to the first and second insulating layers 35 and 38 constituting the first and second outermost layers 31 and 32 to thereby form the amorphous insulating property. The case where a part of the fillers 36 and 39 is protruded from the outer surfaces 35a and 38a has been described as an example. However, the amorphous insulating fillers 36 and 39 include the first and second insulating layers 35 and 38, respectively. What is necessary is just to add only to one insulating layer and arrange | position so that a part may protrude from the outer surface of this insulating layer.

That is, the amorphous insulating fillers 36 and 39 may be added to at least one of the first and second insulating layers 35 and 38.
In this case, the effect similar to that of the terminal film 16 for an electric device according to the present embodiment described above (specifically, the slipping property between the terminal films 16 for an electric storage device in contact is improved (in other words, the antiblocking effect is improved). Effect) can be obtained.
Thereby, it can suppress that a blocking phenomenon generate | occur | produces when pulling out the end of the terminal film 16 for electrical storage devices wound up by roll shape, for example.

  Further, as another effect, for example, the first outermost layer 31 arranged so as to cover a part of the outer peripheral surface of the metal terminal 14 and the packaging material 13 for packaging the power storage device body 11 are arranged. In the case where a resin material having a different characteristic is used as the material of the second outermost layer 32, the first outermost layer 31 that is arranged so as to cover a part of the outer peripheral surface of the metal terminal 14 is formed. The first outermost layer 31 and the second outermost layer 32 can be distinguished by adding an amorphous insulating filler 36 capable of coloring the first insulating layer 36 only to the first insulating layer 36.

In addition, when the amorphous insulating fillers 36 and 39 are added to only one of the first and second insulating layers 35 and 38, and the pigment 42 added to the third insulating layer 41 is carbon. When black is added (in other words, when the intermediate layer 33 has conductivity), the outermost layer including the insulating layer to which the amorphous insulating fillers 36 and 39 are added and the metal terminal 14 are melted. It is good to put on.
Thereby, the insulation between the metal terminal 14 with which the electrical storage device terminal film 16 is fused and the intermediate layer 33 having conductivity can be sufficiently secured.

3 may be fused to the metal terminal 14 in a state where the two terminal films 16 for an electricity storage device shown in FIG. That is, you may arrange | position the two terminal films 16 for electrical storage devices so that the 2nd outermost layer 32 and the metal terminal 14 may contact.
In this case, the same effect as the electricity storage device terminal film 16 of the present embodiment described above can be obtained.

3 and 4, the case where the intermediate layer 33 is colored using the pigment 42 has been described as an example, but the first and second layers are not the third insulating layer 41 constituting the intermediate layer 33. A pigment 42 having no conductivity may be added to at least one of the insulating layers 35 and 38.
In this case, as with the intermediate layer 33 colored with the non-conductive pigment 42, the visibility of the power storage device terminal film 16 can be improved. Accuracy can be improved.

  3 and 4, the power storage device terminal film 16 having a three-layer structure has been described as an example. For example, the intermediate layer 33 and the first outermost layer 31 and the intermediate layer 33 are described. A fourth insulating layer (not shown) made of an insulating resin may be disposed between the first outermost layer 32 and the second outermost layer 32.

  Thus, by disposing a fourth insulating layer (not shown) between the intermediate layer 33 and the first outermost layer 31 and between the intermediate layer 33 and the second outermost layer 32, respectively. Moreover, the insulation between the intermediate layer 33 and the barrier layer 24 (metal layer) constituting the packaging material 13 and the insulation between the intermediate layer 33 and the metal terminal 14 can be improved.

Next, with reference to FIG.3 and FIG.4, the manufacturing method of the terminal film 16 for electrical storage devices of this Embodiment is demonstrated easily.
There is no restriction | limiting in particular in the manufacturing method of the terminal film 16 for electrical storage devices. The power storage device terminal film 16 may be manufactured using, for example, a film extrusion manufacturing apparatus having a die such as a round die used when using the inflation molding method or a T die used when using the press die method. A multi-layer inflation molding method is preferred.

Generally, as the material for the terminal film 16 for an electricity storage device, a material having a melt mass flow rate (hereinafter referred to as “MFR”) of 5 g / 10 min or less is often used. For this reason, when the T-die method is used, the film formation is not stable and the manufacture is often difficult.
On the other hand, the inflation molding method is suitable for the production of the terminal film 16 for an electricity storage device because the film can be stably formed even with the above-mentioned material (a material having an MFR value of 5 g / 10 min or less).

  Moreover, when producing a roll by the inflation molding method, it is common to wrap and convey the tube, cut the end immediately before winding, and divide the roll into two rolls. By improving the slidability between the terminal films 16 for the electricity storage device, it is possible to improve the slidability inside the tube at the time of transportation, and to improve conveyance wrinkles and breakage. Can be improved.

  In the following description, as an example of a method for manufacturing the electricity storage device terminal film 16, a case in which the electricity storage device terminal film 16 is produced using an inflation molding method (in other words, an inflation molding apparatus) will be described.

First, the base materials of the first outermost layer 31, the second outermost layer 32, and the intermediate layer 33 are prepared.
Specifically, as the base material of the first outermost layer 31, an amorphous insulating filler 36 is added to a melted insulating resin to be the first insulating layer 35 so that a predetermined addition amount is obtained. An insulating filler-containing resin kneaded uniformly is prepared.
In addition, as a base material of the second outermost layer 32, an insulating filler 39 is uniformly kneaded so that a predetermined addition amount is obtained by melting an insulating resin to be the second insulating layer 38. An insulating filler-containing resin is prepared.

  Also, as the base material of the intermediate layer 33, a pigment-containing resin in which the pigment 42 is uniformly kneaded so as to have a predetermined addition amount prepared by melting the insulating resin to be the third insulating layer 41 is prepared. To do.

Next, the base materials of the first outermost layer 31, the second outermost layer 32, and the intermediate layer 33 are supplied to an inflation molding apparatus (not shown).
Next, while extruding the three base materials from the extrusion part of the inflation molding apparatus so as to have a three-layer structure (a structure in which the first outermost layer 31, the second outermost layer 32, and the intermediate layer 33 are laminated). Then, air is supplied from the inside of the extruded laminate having the three-layer structure.

  Then, while conveying the cylindrical power storage device terminal film 16 inflated into a cylindrical shape, it is deformed into a flat shape by the guide portion, and then the power storage device terminal film 16 is folded into a sheet shape by a pair of pinch rolls. . The both ends of the woven tube are slit, and a pair of (two strips) films are wound up in a roll shape around a winding core, whereby the roll-shaped power storage device terminal film 16 is manufactured.

The extrusion temperature when producing the terminal film 16 for an electricity storage device is preferably in the range of 170 to 300 ° C, and more preferably 200 to 250 ° C, for example.
When the extrusion temperature is less than 170 ° C., the melt of the insulating resin becomes insufficient, and the melt viscosity becomes considerably large, so that the extrusion from the screw may be unstable.
On the other hand, when the extrusion temperature exceeds 300 ° C., oxidation and deterioration of the insulating resin become severe, so that the quality of the terminal film 16 for power storage device is deteriorated.

  The number of rotations of the screw, the blow ratio, the take-off speed, etc. can be appropriately set in consideration of the set film thickness. Moreover, the film thickness ratio of each layer of the terminal film 16 for electrical storage devices can be easily adjusted by changing the rotation speed of each screw.

  In addition, you may manufacture the terminal film 16 for electrical storage devices of this Embodiment using the method of laminating | stacking the insulating layers (insulating film) formed into a film by the dry lamination using an adhesive agent, or sandwich lamination.

Here, with reference to FIG. 3, the fusion | melting process which melt-bonds the terminal film 16 for electrical storage devices and the metal terminal 14 of this Embodiment is demonstrated.
In the fusing process, the first outermost layer 31 is melted by heating, and the first outermost layer 31 and the metal terminal 14 are simultaneously bonded by pressurization. Is heat-sealed.

  Moreover, in the said heat sheet process, in order to acquire sufficient adhesiveness and sealing performance of the terminal film 16 for electrical storage devices and the metal terminal 14, insulating resin (1st insulating layer) which comprises the 1st outermost layer 31 35 base material) is heated to a temperature equal to or higher than the melting point.

  Specifically, for example, 140 to 170 ° C. can be used with the power storage device terminal film 16 as a heating temperature. Further, the treatment time (total time of heating time and pressurization time) needs to be determined in consideration of the peel strength and productivity. The processing time can be appropriately set within a range of 1 to 60 seconds, for example.

  In addition, when giving priority to the production tact (productivity) of the terminal film 16 for electrical storage devices, you may heat-seal | fuse at a temperature exceeding 170 degreeC for a short pressurization time. In this case, for example, 170 to 200 ° C. can be used as the heating temperature, and 3 to 20 seconds can be used as the pressurizing time, for example.

  The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to such specific embodiments, and within the scope of the present invention described in the claims, Various modifications and changes are possible.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

Example 1
<Preparation of positive electrode tab and negative electrode tab>
Referring to FIG. 3, the positive electrode tab and the negative electrode tab of Example 1 (in other words, metal terminal 14 (also referred to as “tab lead”) and a pair of power storage device terminal films 16 (also referred to as “tab sealant”). A manufacturing method of the structure will be described.

  First, an aluminum thin plate member having a width of 5 mm, a length of 20 mm, and a thickness of 100 μm is prepared as the metal terminal main body 14-1 for the positive electrode. Next, non-chromium surface treatment is performed on the surface of the aluminum thin plate member to form a corrosion prevention layer 14-2 (non-chromium surface treatment layer), so that the aluminum thin plate member and the non-chromium-based member are formed. A positive-side metal terminal 14 including a surface treatment layer (hereinafter, referred to as “positive-electrode metal terminal 14A”) was produced.

  Next, a nickel thin plate member having a width of 5 mm, a length of 20 mm, and a thickness of 100 μm is prepared as the negative electrode metal terminal main body 14-1, and then non-chromium is applied to the surface of the nickel thin plate member. By carrying out the system surface treatment to form a corrosion prevention layer 14-2 (non-chromium-based surface treatment layer), the nickel-made thin plate member and the metal terminal 14 on the negative electrode side including the non-chromium-based surface treatment layer (hereinafter, For convenience of explanation, a “negative electrode metal terminal 14B” was prepared.

  Next, amorphous silica having an average particle diameter of 5.0 μm (amorphous insulation) with a concentration of 5.0 wt% with respect to the acid-modified polypropylene that is the base material of the first insulating layer 35. The base material of the 1st outermost layer 31 was produced by adding and mixing the property filler 36).

Next, amorphous silica having an average particle diameter of 5.0 μm (amorphous insulation) with a concentration of 5.0 wt% with respect to the acid-modified polypropylene which is the base material of the second insulating layer 38. The base material of the second outermost layer 32 was produced by adding and mixing the conductive filler 39).
Next, carbon black (pigment 42) having an average particle size of 50 nm is added to and mixed with polypropylene as a base material of the intermediate layer 33 so that the concentration becomes 0.1 wt%. A base material for the layer 33 was produced.

Next, the base material of the first outermost layer 31, the base material of the second outermost layer 32, and the base material of the intermediate layer 33 are put into an inflation type film extrusion manufacturing apparatus (Co-OI type) manufactured by Sumitomo Heavy Industries Modern Co., Ltd. The laminated film (film serving as the base material of the power storage device terminal film 16) was prepared by setting and extruding the three base materials with the film extrusion manufacturing apparatus.
At this time, the laminated film was formed so that the thickness of the first insulating layer 35 was 30 μm, the thickness of the second insulating layer 38 was 30 μm, and the thickness of the third insulating layer 41 was 40 μm.
The melting temperature of the base material of the first outermost layer 31, the base material of the second outermost layer 32, and the base material of the intermediate layer 33 was 210 ° C. The blow ratio was set to 2.2.

Next, by cutting the laminated film, four power storage device terminal films 16 having a width of 9 mm and a length of 5 mm were produced.
Thereafter, the positive electrode metal terminal 14A is sandwiched between the two power storage device terminal films 16, and the two power storage device terminal films 16 are heated at a heating temperature of 155 ° C. for 10 seconds to obtain the positive metal terminal 14A. And two sheets of storage device terminal film 16 were heat-sealed to prepare a positive electrode tab including the positive electrode metal terminal 14 </ b> A and the two storage device terminal films 16.

  Next, the negative electrode metal terminal 14B and the two electric storage devices are bonded by heat-sealing the negative electrode metal terminal 14B and the two electric storage device terminal films 16 sandwiching the negative electrode metal terminal 14B in the same manner. A negative electrode tab made of the terminal film 16 was prepared.

<Preparation of battery pack for evaluation>
Next, a 25 μm thick nylon layer (outer layer 26), a 5 μm thick polyester polyol-based adhesive (outer layer side adhesive layer 25), and an aluminum foil (barrier layer 24) that is an A8079-O material having a thickness of 40 μm. A first corrosion prevention treatment layer (corrosion prevention treatment layer 23-1) formed by subjecting one surface of the aluminum foil to a non-chromium surface treatment, and a non-chromium surface treatment of the other surface of the aluminum foil. A second corrosion prevention treatment layer (corrosion prevention treatment layer 23-2) to be formed, a 30 μm thick acid-modified polypropylene layer (inner layer side adhesive layer 22), and a 40 μm thick polypropylene layer (inner layer 21) And a packaging material 13 having a rectangular shape with a size of 50 mm × 90 mm was prepared.

  Next, the packaging material 13 and the positive electrode are folded by folding at the midpoint of the long side of the packaging material 13 and sandwiching the positive electrode tab and the negative electrode tab on one of the two folded portions having a length of 45 mm. The tab for use and the tab for negative electrode were fused. At this time, the heat sealing conditions were a heating temperature of 190 ° C. and a treatment time of 5 seconds.

Thereafter, 2 mL of an electrolytic solution in which lithium hexafluorophosphate was added to a mixed solution of diethyl carbonate and ethylene carbonate was filled in the packaging material 13.
Next, the remaining side of the packaging material 13 was heat-sealed. The heat sealing conditions at this time were a heating temperature of 190 ° C. and a processing time of 3 seconds.
As a result, a battery pack capable of tab evaluation in which the power storage device main body 11 was not enclosed was produced.

(Example 2)
In Example 2, the laminated film of Example 2 (terminal for electricity storage device) was obtained in the same manner as the laminated film of Example 1 except that the amorphous insulating filler 36 was not added to the first insulating layer 35. Film to be a base material of film 16) was produced.
Thereafter, an evaluation battery pack of Example 2 was produced in the same manner as in Example 1.

(Example 3)
In Example 3, the laminated film (terminal for power storage device) of Example 3 was obtained in the same manner as the laminated film of Example 1 except that the amorphous insulating filler 39 was not added to the second insulating layer 38. Film to be a base material of film 16) was produced.
Thereafter, an evaluation battery pack of Example 3 was produced in the same manner as in Example 1.

Example 4
In Example 4, the implementation was performed except that the average particle diameter of the amorphous insulating fillers 36 and 39 was changed to 3.0 μm, and the additive concentration of the amorphous insulating fillers 36 and 39 was changed to 10.0 wt%. A laminated film of Example 4 (a film serving as a base material of the electricity storage device terminal film 16) was produced in the same manner as the laminated film of Example 1.
Thereafter, an evaluation battery pack of Example 4 was produced in the same manner as in Example 1.

(Example 5)
In Example 5, the implementation was performed except that the average particle diameter of the amorphous insulating fillers 36 and 39 was changed to 10.0 μm and the additive concentration of the amorphous insulating fillers 36 and 39 was changed to 2.0 wt%. A laminated film of Example 5 (film serving as a base material for the storage device terminal film 16) was produced in the same manner as the laminated film of Example 1.
Thereafter, an evaluation battery pack of Example 5 was produced in the same manner as in Example 1.

(Example 6)
Example 6 is the same as the laminated film of Example 1 except that the thickness of the first and second insulating layers 35 and 38 is 10 μm and the thickness of the third insulating layer 41 is 20 μm. The laminated film of Example 6 (film that becomes a base material of the terminal film 16 for an electricity storage device) was produced by various techniques.
Thereafter, an evaluation battery pack of Example 6 was produced in the same manner as in Example 1.

(Example 7)
In Example 7, the thickness of the first and second insulating layers 35 and 38 is 40 μm, the thickness of the third insulating layer 41 is 20 μm, and the average particle size of the amorphous insulating fillers 36 and 39 is 3.0 μm. A laminated film of Example 7 (a film serving as a base material for the electricity storage device terminal film 16) was produced in the same manner as in the laminated film of Example 1 except that the above was performed.
Thereafter, an evaluation battery pack of Example 7 was produced in the same manner as in Example 1.

(Example 8)
In Example 8, the laminated film of Example 8 was prepared in the same manner as the laminated film of Example 1 except that 0.5 wt% carbon black (pigment 42) was contained in the third insulating layer 41. A film serving as a base material of the terminal film 16 for an electricity storage device) was produced.
Thereafter, an evaluation battery pack of Example 8 was produced in the same manner as in Example 1.

Example 9
In Example 9, the average particle size of the amorphous insulating fillers 36 and 39 is changed to 1.0 μm, and carbon black (pigment 42) is added to the third insulating layer 41 so as to have a concentration of 0.01 wt%. A laminated film of Example 9 (film serving as a base material for the terminal film 16 for an electricity storage device) was produced in the same manner as the laminated film of Example 1 except that it was included.
Thereafter, an evaluation battery pack of Example 9 was produced in the same manner as in Example 1.

(Example 10)
In Example 10, Example 3 was performed in the same manner as the laminated film of Example 1 except that phthalocyanine blue (pigment 42) was contained in the third insulating layer 41 so as to have a concentration of 0.2 wt%. 10 laminated films (films serving as base materials for the terminal film 16 for power storage devices) were produced.
Thereafter, an evaluation battery pack of Example 10 was produced in the same manner as in Example 1.

(Example 11)
In Example 11, the laminated film of Example 11 (in the same manner as the laminated film of Example 1 except that 0.2 wt% titanium dioxide (pigment 42) was contained in the third insulating layer 41) A film serving as a base material of the terminal film 16 for an electricity storage device) was produced.
Thereafter, an evaluation battery pack of Example 11 was produced in the same manner as in Example 1.

(Example 12)
In Example 12, the laminated film (Example 12) of Example 12 was prepared in the same manner as the laminated film of Example 1 except that a polypropylene layer (10 μm) was provided between the intermediate layer 33 and the second outermost layer 32. A film serving as a base material of the terminal film 16 for an electricity storage device) was produced.
Thereafter, an evaluation battery pack of Example 12 was produced in the same manner as in Example 1.

(Example 13)
In Example 13, the average particle size of the amorphous insulating fillers 36 and 39 was set to 0.03 μm, and carbon black was not added to the third insulating layer 41, and was the same as the laminated film of Example 1. By the method, the laminated film of Example 13 (film serving as a base material for a terminal film for an electricity storage device) was produced.
Thereafter, an evaluation battery pack of Example 13 was produced in the same manner as in Example 1.

(Example 14)
In Example 14, the laminated film (terminal film for power storage device) of Example 14 was prepared in the same manner as the laminated film of Example 1 except that the concentration of the amorphous insulating fillers 36 and 39 was 0.03 wt%. Film as a base material).
Thereafter, an evaluation battery pack of Example 14 was produced in the same manner as in Example 1.

(Example 15)
In Example 15, the concentration of the amorphous insulating fillers 36 and 39 was set to 0.03 wt%, and 5.0 wt% of carbon black (pigment 42) was added to the insulating layer 41. A laminated film of Example 15 (film serving as a base material for an electricity storage device terminal film) was produced in the same manner as the laminated film.
Thereafter, an evaluation battery pack of Example 15 was produced in the same manner as in Example 1.

(Example 16)
In Example 16, the thickness of the first and second insulating layers 35 and 38 is 15 μm, the thickness of the third insulating layer 41 is 30 μm, and the average particle size of the amorphous insulating fillers 36 and 39 is 10.0 μm. In the same manner as the laminated film of Example 16, except that carbon black was not added to the third insulating layer 41, the laminated film of Example 16 (film serving as a base material for the terminal film for power storage devices) ) Was produced.
Thereafter, an evaluation battery pack of Example 16 was produced in the same manner as in Example 1.

(Example 17)
In Example 17, except that the average particle size of the amorphous insulating fillers 36 and 39 was 25.0 μm, the laminated film of Example 17 (terminal for power storage device) was obtained in the same manner as the laminated film of Example 1. Film as a base material of the film) was prepared.
Thereafter, an evaluation battery pack of Example 17 was produced in the same manner as in Example 1.

(Comparative Example 1)
In Comparative Example 1, the first outermost layer 31 is formed of only the first insulating layer 35 without using the amorphous insulating fillers 36 and 39, and the second outermost layer 32 is formed of only the second insulating layer 38. A laminated film of Comparative Example 1 (a film serving as a base material for a terminal film for an electricity storage device) was produced in the same manner as the laminated film of Example 1 except that the film was formed as described above.
Thereafter, an evaluation battery pack of Comparative Example 1 was produced in the same manner as in Example 1.

(Comparative Example 2)
In Comparative Example 2, spherical silica having an average particle diameter of 0.5 μm was used in place of the amorphous insulating fillers 36 and 39, and the spherical silica was added so that the concentration of the spherical silica was 2 wt%. Then, a laminated film of Comparative Example 2 (film serving as a base material for a terminal film for an electricity storage device) was produced in the same manner as the laminated film of Example 1.
Thereafter, an evaluation battery pack of Comparative Example 2 was produced in the same manner as in Example 1.

<Evaluation of anti-blocking property (AB property) of laminated films of Examples 1 to 17 and laminated films of Comparative Examples 1 and 2>
First, after laminating the laminated film (base material of the electricity storage device terminal film 16) produced in Example 1 with the first outermost layers 31 facing each other, a pressure of 0.5 MPa was applied, and the temperature Was stored for 24 hours in an environment of 40 ° C., and the degree of peeling of the laminated film was confirmed.
As the evaluation of anti-blocking property (AB property), ◎ indicates that the material was peeled without resistance, ○ indicates that the material was peeled off slightly, but x indicates that the material was peeled off when it was difficult to peel off.

Subsequently, the antiblocking property of the laminated film of Examples 2-17 and the laminated film of Comparative Examples 1 and 2 was evaluated by the same method as the method for evaluating the antiblocking property of the laminated film of Example 1.
In Table 1, the evaluation result (judgment result) of the antiblocking property of the laminated film of Examples 1-17 and the laminated film of Comparative Examples 1 and 2 is shown.
Table 1 also shows the thickness of each layer constituting the laminated films of Examples 1 to 17 and the laminated films of Comparative Examples 1 and 2, the type and average particle size of the insulating filler, and the pigment (specifically, The concentration of carbon black, phthalocyanine blue, and titanium oxide) is also shown.

<Evaluation test of adhesion of evaluation battery packs of Examples 1 to 17 and evaluation battery packs of Comparative Examples 1 and 2>
100 samples of each of the evaluation battery packs of Examples 1 to 17 and the evaluation battery packs of Comparative Examples 1 and 2 were prepared, and then 100 samples of Examples 1 to 17 were placed in a room maintained at a temperature of 80 ° C. The battery pack for evaluation and the battery pack for evaluation of Comparative Examples 1 and 2 were stored for 4 weeks, and the presence or absence of leakage of the enclosed electrolyte was confirmed.
In this evaluation, ◎ indicates that no liquid leakage was confirmed, and x indicates that liquid leakage was confirmed.
Table 1 shows the evaluation results (determination results) of the adhesion of the evaluation battery packs of Examples 1 to 17 and the evaluation battery packs of Comparative Examples 1 and 2.

<Insulation evaluation test of evaluation battery packs of Examples 1 to 17 and evaluation battery packs of Comparative Examples 1 and 2>
First, 100 specimens of the evaluation battery pack of Example 1 were prepared, and then using the withstand voltage / insulation resistance tester, the negative electrode metal terminal 14B and the packaging material 13 constituting the evaluation battery pack of Example 1 were prepared. The insulation between was measured. The insulation measurement was performed on the 100 specimens. At this time, the case where no short-circuit occurred was judged as ◎, the case where the number of short-circuited samples was less than 10 was marked as ◯, and the case where the number of short-circuited samples was confirmed as 10 or more was judged as x. did.

Next, 100 samples of each of the evaluation battery packs of Examples 2 to 17 and the evaluation battery packs of Comparative Examples 1 and 2 were prepared, and by the same method as the insulation evaluation test of the evaluation battery pack of Example 1, Insulation was evaluated.
Table 1 shows the evaluation results (judgment results) of the insulation battery packs of Examples 1 to 17 and the evaluation battery packs of Comparative Examples 1 and 2.

<Evaluation test of sensing properties of negative electrode tab and positive electrode tab of Examples 1 to 17 and negative electrode tab and positive electrode tab of Comparative Examples 1 and 2>
First, 500 specimens of the evaluation battery pack of Example 1 were prepared, and then the negative electrode tab and the positive electrode tab detected by the detector using an imaging detector (CV-X100, manufactured by Keyence Corporation). The detection rate (sensing property) was obtained.
With respect to the detection rate, those having a detection rate of 95% or more were evaluated as ◎, those having a detection rate of less than 95% and 90% or more were evaluated as ○, and those having a detection rate of less than 90% were determined as ×.

Next, 500 samples of the evaluation battery packs of Examples 2 to 17 and the evaluation battery packs of Comparative Examples 1 and 2 were prepared, respectively, and the same as in the sensing property evaluation test of the negative electrode tab and the positive electrode tab of Example 1 The sensing properties of the negative electrode tab and the positive electrode tab constituting the evaluation battery packs of Examples 2 to 17 and Comparative Examples 1 and 2 were evaluated by the method.
Table 1 shows the evaluation results (determination results) of the sensing properties of the negative electrode tab and the positive electrode tab of Examples 1 to 17 and the evaluation results of the sensing properties of the negative electrode tab and the positive electrode tab of Comparative Examples 1 and 2 (determination). Results).

<Summary of evaluation results shown in Table 1>
Referring to Table 1, from the evaluation results of Examples 1 to 3 and Comparative Example 1, when there is no amorphous silica in both the first and second outermost layers 31 and 32, the anti-blocking property of the laminated film It was confirmed that the sensing properties of the negative electrode tab and the positive electrode tab were lowered.
Moreover, it has confirmed from the evaluation result of the comparative example 2 using spherical silica that the antiblocking property of a laminated film will worsen when spherical silica is used.
Therefore, from the evaluation results of Examples 1 to 3 and Comparative Examples 1 and 2, in order to improve the anti-blocking property of the laminated film and increase the sensing properties of the negative electrode tab and the positive electrode tab, It has been confirmed that at least one of the second outermost layers needs to contain amorphous silica.

From the evaluation results of Examples 9 and 13, the average particle diameter of amorphous silica is too small with respect to the thickness of the first and second insulating layers (in this case, 0.03 μm (value of Example 13)). It was confirmed that the determination result of anti-blocking property was reduced from ◎ (evaluation result of Example 9 in which the average particle size of amorphous silica was 1.0 μm) to ○ (evaluation result of Example 13). .
From this, it was confirmed that the average particle diameter of the amorphous silica is preferably larger than 0.03 μm.

From the evaluation results of Examples 5 and 17, when the average particle size of the amorphous silica is too large (in this case, 25.0 μm) relative to the thickness of the first and second insulating layers, the anti-blocking property is determined. Although the result was very good, it was confirmed that the adhesion evaluation was changed from ◎ (evaluation result of Example 5) to x (evaluation result of Example 17).
From this result, it was confirmed that the average particle diameter of the amorphous silica is preferably smaller than 25.0 μm.

  From the evaluation results of Examples 1 to 9, when the average particle size of the amorphous insulating filler is in the range of 1.0 to 10.0 μm, anti-blocking property, adhesion, insulating property, and sensing property are obtained. In all items, it was confirmed that very good results (all results are ◎) were obtained.

  From the evaluation results of Examples 6 and 9, the thickness of the first and second insulating layers 35 and 38 containing amorphous silica is a value within a range of 2 to 30 times the average particle diameter of the amorphous silica. As a result, very good results (all results are ◎) were obtained in all items of anti-blocking properties, adhesion properties, insulating properties, and sensing properties.

From the results of Examples 1 to 9, 13, and 16, if the third insulating layer does not contain carbon black, the sensing property judgment result is poor (in other words, the judgment result is x), and the third insulating layer It was confirmed that when the carbon black contained 0.01 to 0.5 wt%, the sensing property judgment result was very good (in other words, the judgment result was ◎).
From this, it was found that when 0.01 wt% or more of carbon black is contained in the third insulating layer, the sensing result is very good (in other words, the judgment result is ◎).

From the evaluation results of Examples 1, 5, and 14, when the addition amount of the amorphous insulating filler is 0.03 wt%, the determination result of the anti-blocking property may be lowered (in other words, the determination result is ◯). understood.
From the evaluation results of Examples 10 and 11, it was confirmed that phthalocyanine blue or titanium dioxide may be used instead of carbon black.
The anti-blocking property determination results of Examples 1 to 17 were ◯ or ◎, and good results were obtained.

  The present invention relates to a power storage device terminal film interposed between a packaging material for packaging a power storage device body, and a metal terminal electrically connected to the power storage device body and extending to the outside of the packaging material, and The present invention can be applied to an electricity storage device having the electricity storage device terminal film.

  DESCRIPTION OF SYMBOLS 10 ... Electric storage device, 11 ... Electric storage device main body, 13 ... Packaging material, 14 ... Metal terminal, 14-1 ... Metal terminal main body, 14-2 ... Corrosion prevention layer, 16 ... Terminal film for electric storage device, 21 ... Inner layer, 22 ... inner layer side adhesive layer, 23-1, 23-2 ... corrosion prevention treatment layer, 24 ... barrier layer, 25 ... outer layer side adhesive layer, 26 ... outer layer, 31 ... first outermost layer, 32 ... second Outermost layer, 33 ... intermediate layer, 35 ... first insulating layer, 35a, 38a ... outer surface, 36,39 ... amorphous insulating filler, 38 ... second insulating layer, 41 ... third insulating layer, 42 ... Pigment

Claims (9)

An electricity storage device terminal film arranged to cover a part of the outer peripheral surface of a metal terminal electrically connected to an electricity storage device body constituting the electricity storage device,
A first outermost layer including a first insulating layer;
A second outermost layer including a second insulating layer;
An amorphous insulating filler added to at least one of the first and second insulating layers;
Have
A terminal film for an electricity storage device, wherein a part of the amorphous insulating filler is disposed so as to protrude from the outer surface of the insulating layer.   The terminal film for an electricity storage device according to claim 1, wherein an average particle diameter of the amorphous insulating filler is in a range of 0.1 to 20 μm.   3. The thickness of the insulating layer to which the amorphous insulating filler is added is 2 to 30 times the average particle size of the amorphous insulating filler. Terminal film for electricity storage devices.   The terminal film for an electricity storage device according to any one of claims 1 to 3, wherein the amount of the amorphous insulating filler added is 0.1 to 20 wt%.   The terminal film for an electricity storage device according to any one of claims 1 to 4, wherein the amorphous filler is added only to one of the first and second insulating layers.   A third insulating layer disposed between the first outermost layer and the second outermost layer, and an intermediate layer containing a pigment added to the third insulating layer. Item 6. The power storage device terminal film according to any one of Items 1 to 5.   The power storage device according to claim 6, wherein a fourth insulating layer is disposed between the intermediate layer and the first outermost layer and between the intermediate layer and the second outermost layer. Terminal film for devices. The terminal film for an electricity storage device according to any one of claims 1 to 7,
A power storage device body to be charged and discharged;
A pair of the metal terminals that are electrically connected to the power storage device body and partially covered with the terminal film for the power storage device,
A part of the terminal film for the electricity storage device, and a packaging material covering the electricity storage device body,
An electricity storage device comprising:   Of the first and second outermost layers, one outermost layer is disposed so as to cover a part of the outer peripheral surface of the metal terminal, and the other outermost layer is disposed so as to contact the packaging material. The power storage device according to claim 8.

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