KR102121675B1 - Lead wires and electrical components for electrical components - Google Patents

Abstract

The lead wire for an electrical component according to an embodiment of the present invention includes a strip-shaped conductor and a pair of insulating films covering both sides of the strip-shaped conductor, and the elastic modulus of the strip-shaped conductor is D _m [㎩], width 1 The cross-sectional secondary moment per mm is I _m [m ⁴ /1 mm], the average elastic modulus of the pair of insulating films is D _i [ _i ], and the cross-sectional secondary moment per 1 mm width is I _i [m ⁴ /1 mm], the width of the insulating film represented by the formula (2) for the shape-retaining force H [N·m 2 /1 mm] per 1 mm of the width of the strip-shaped conductor represented by the formula (1) is 1 mm. The ratio (R/H) of the elastic recovery force R [N·m 2/1 mm] of the sugar is 0.15 or less.
H=D _m ×I _m … (One)
R=D _i ×I _i … (2)

Description

Lead wires and electrical components for electrical components

The present invention relates to an electrical component lead wire and an electrical component.

With the demand for downsizing of electronic devices, there is a strong demand for downsizing and weight reduction of batteries used as power sources. Meanwhile, high energy density and high energy efficiency for batteries are also required. In order to satisfy such a demand, expectations for a nonaqueous electrolyte battery (for example, a lithium ion battery, etc.) in which an electrode, an electrolyte, and the like are sealed inside the encapsulation body are increasing.

In such a non-aqueous electrolyte battery, it is common for lead wires to extend from the encapsulating body in order to draw current to the outside. As a lead wire, it is known that the lead conductor is made of only a metal lead conductor such as aluminum, and the lead conductor is covered with an insulating layer of a thermoplastic resin. Then, the lead wire is attached to the encapsulation body by, for example, heat sealing the opening end portion with the lead wire interposed therebetween by the inner surface of the opening end portion of the encapsulation body.

In the method of attaching the lead conductor to the encapsulation body by such heat sealing, there is a possibility that the insulating layer is melted by heat during heat sealing, so that the lead conductor is shorted with the metal layer of the encapsulation body. Therefore, it is proposed to avoid melting of the insulating layer by making the insulating layer include a crosslinked layer made of crosslinked polyolefin (for example, see Patent Documents 1 and 2).

Patent Document 1: Japanese Patent Publication No. 2001-102016 Patent Document 2: Japanese Patent Publication No. 2009-259739

The lead wire for an electrical component according to one embodiment of the present invention is a lead wire for an electrical component including a strip-shaped conductor and a pair of insulating films covering both surfaces of the strip-shaped conductor, the strip shape The elastic modulus of the conductor is D _m [㎩], the second moment of inertia of area per 1 mm of width is I _m [m ⁴ /1 mm], and the pair of insulating films When the average modulus of elasticity is D _i [㎩] and the cross-sectional secondary moment per 1 mm of width is I _i [m ⁴ /1 mm], the shape-retaining force per 1 mm of width of the strip-shaped conductor represented by the following formula (1) The ratio (R/H) of the elastic recovery force R [N·m 2/1 mm] per 1 mm of width of the insulating film represented by the following formula (2) to H [N·m 2/1 mm] is 0.15 or less.

H=D _m ×I _m … (One)

R=D _i ×I _i … (2)

An electrical component according to one embodiment of the present invention includes a lead wire for the electrical component.

1 is a schematic perspective view of a portion for explaining an example of a lithium ion battery according to another embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view taken along line AA in FIG. 1.
FIG. 3(a) is a schematic cross-sectional view as viewed in the longitudinal direction for explaining the cross-sectional secondary moment of the strip-shaped conductor and the insulating film in the lead wire for an electrical component according to one embodiment of the present invention.
Fig. 3(b) is a schematic cross-sectional view showing only the strip-shaped conductor of the lead wire for an electric component of Fig. 3(a).
Fig. 3(c) is a schematic cross-sectional view showing only the insulating film of the lead wire for an electric component in Fig. 3(a).
4(a) is a schematic plan view for explaining a lead wire used for evaluation of a spring back angle.
4(b) is a schematic cross-sectional view of the lead wire of FIG. 4(a).
5(a) is a schematic cross-sectional view for explaining one step of the method for evaluating the spring back angle.
Fig. 5(b) is a schematic cross-sectional view for explaining the next step of Fig. 5(a).
Fig. 6 is a graph showing the relationship between the result of measuring the spring back angle and the ratio (R/H) of the elastic recovery force R per 1 mm width of a pair of insulating films to the shape holding force H per 1 mm width of the strip-shaped conductor. .

[Tasks to be solved by this disclosure]

The non-aqueous electrolyte battery having the conventional lead wire is often stored in an electronic device with the lead wire bent. Therefore, in the manufacture of the electronic device, the lead wire provided in the nonaqueous electrolyte battery may be bent at a location where the lead conductor is covered with an insulating layer, and may be sent to a downstream process while maintaining the bent shape. Therefore, when it is assumed that the lead wire is bent and used, a spring wire is unlikely to be generated, and a lead wire capable of properly maintaining the bent shape is required.

Here, the lead conductor is a metal such as aluminum, plastically deformed when bent, and generates a force to maintain the bent shape. On the other hand, since the insulating layer is made of resin or the like, it is elastically deformed when it is bent, and a force is generated to return to the original shape from the bent shape. Of these two forces, when the force to return to the original shape from the bending shape due to the elastic deformation of the insulating layer acts strongly, the lead wire cannot maintain the bending shape and returns to a slightly original shape (spring White). However, the spring back is a complex phenomenon caused by the interaction of two members having different materials, such as a metal lead conductor and a resin insulating layer, so that any member applied to the lead conductor and the insulating layer can sufficiently suppress the spring back. It is difficult to accurately predict whether there will be.

An object of the present invention is to provide a lead wire for an electric component and an electric component that are unlikely to generate a spring back when bent and are used, and which can properly maintain the bending shape.

[Effects of the Invention]

ADVANTAGE OF THE INVENTION According to the said invention, when a bend is used, it is difficult to produce a spring back, and it is possible to provide a lead wire for an electric component capable of properly maintaining a bent shape, and an electric component excellent in working efficiency.

[Description of embodiments of the present invention]

The lead wire for an electrical component according to one embodiment of the present invention is a lead wire for an electrical component comprising a strip-shaped conductor and a pair of insulating films covering both surfaces of the strip-shaped conductor, wherein the elastic modulus of the strip-shaped conductor is D _m [㎩], the cross-sectional secondary moment per 1 mm of width is I _m [m ⁴ /1 mm], and the average elastic modulus of the pair of insulating films is D _i [㎩], the cross-sectional secondary moment per 1 mm of width In the case of I _i [m ⁴ /1 mm], in the following formula (2) for the shape retention force H [N·m 2 /1 mm] per 1 mm of width of the strip-shaped conductor represented by the following formula (1) The ratio (R/H) of the elastic recovery force R [N·m 2/1 mm] per 1 mm of width of the insulating film shown is 0.15 or less.

H=D _m ×I _m … (One)

R=D _i ×I _i … (2)

Here, the reason why the springback occurs in the lead wire is that, rather than the force to maintain the bending shape due to the plastic deformation of the strip-shaped conductor as described above, it is intended to return to the original shape from the bending shape due to the elastic deformation of the insulating film. It is thought that it is because the force acts strongly. Therefore, it is considered that if the force due to the plastic deformation of the strip-shaped conductor is increased, while the force due to the elastic deformation of the insulating film is reduced, the springback is suppressed and the bending shape of the lead wire is easily maintained. Here, it is considered that whether the lead wire can maintain a bent shape, that is, the ease of generating the spring back depends not only on the material of the strip-shaped conductor or the insulating film, but also on their thickness and shape. Therefore, the present inventors, etc., the shape per 1 mm of width represented by the above formula (1), which has the effect of the strip-shaped conductor of the lead wire for the electrical component on the spring back as its parameter of the modulus of elasticity and the secondary moment of section per 1 mm of width. We found that we can judge by holding power. In addition, the inventors of the present invention, etc., have the effect of the insulating film of the lead wire for the electrical component on the spring back, the elastic modulus and the elastic recovery force per 1 mm of width represented by Equation (2) above as the parameters of the second moment of section per 1 mm of width. We found that we can judge by. In addition, the inventors of the present invention have an elastic recovery force per 1 mm width of a pair of insulating films with respect to the shape retaining force per 1 mm width of the strip-shaped conductors. It was found that the springback is unlikely to occur when bent and used when the ratio is less than or equal to the above upper limit, and the bending shape can be appropriately maintained.

In this way, the lead wire for the electrical component is less likely to have a springback by making the ratio of the elastic recovery force per 1 mm width of the pair of insulating films to the shape retention force per 1 mm width of the strip-shaped conductor to be less than the above upper limit, and thus to form a bending shape. It can be maintained properly. For this reason, when the lead wire is bent and used, the bending shape is maintained and easy, so that the bent lead wire does not need to be fixed to other elements using a fixing tape or the like after bending the lead wire. As a result, the lead wire for electric parts can simplify the manufacturing process in the case of bending and use, and can also contribute to space saving by bending and using.

Here, "average thickness" means the average value of the thickness measured at arbitrary five points. The term "elastic modulus" refers to an upward slope of an SS curve (stress-strain curve) when tensile deformation is applied to a strip-shaped conductor and an insulating film using a precision universal testing instrument (precision testing machine). Indicates. In the measurement of this modulus of elasticity, the sample gripping (chuck) interval of the tensile testing machine is set to 50 mm, and the tension is set to 50 mm/min. However, when measuring the elastic modulus of the strip-shaped conductor, in order to consider the effect of slipping between the sample and the gripper of the tester, it is assumed that a strain gauge capable of measuring micro-displacement is provided on the sample and measured. In addition, although the test force [N]-travel distance [mm] curve is obtained directly from the measurement of the elastic modulus, the stress [㎩] is obtained using the sample size and chuck spacing as shown in the following equations (3) and (4). It is assumed that the elastic modulus is obtained by converting to a ]-strain [%] curve. Further, even when the strip-shaped conductor and the insulating film are multi-layer structures, the elastic modulus can be obtained by the above-described method. In addition, "average elastic modulus of a pair of insulating films" means the average of the measured values of each elastic modulus of two insulating films. Hereinafter, in the case of "average thickness" or "elastic modulus", it is defined similarly.

Stress [㎩] = Test force [N] ÷ Width [㎜] ÷ Thickness [㎜]… (3)

Deformation [%] = Travel distance [㎜]÷ Chuck spacing [㎜]×100… (4)

It is preferable that the lead wire for the electric component has a bending restoration angle of 20° or less after bending 180°. According to such a lead wire, since the bending restoration angle after being bent 180°, i.e., the spring back angle is 20° or less, the bending shape can be more appropriately maintained, it becomes easier to bend the lead wire and maintain the shape. Workability is improved more.

The elastic recovery force R is preferably 3.0 x 10 ^-5 N·m2/1 mm or more and 6.0 x 10 ^-3 Nm2/1 mm or less. According to such a lead wire, when the said elastic recovery force R is the said range, the spring back after the said lead wire for electrical components is bent can be made appropriately small. As a result, the bending operation of the lead wire for electrical parts becomes easier, and workability is further improved.

As the shape holding force H, 3.0 x 10 ^-4 N·m2/1 mm or more and preferably 6.0 x 10 ^-2 N·m2/1 mm or less. According to such a lead wire, since the bend shape can be more appropriately maintained when the shape holding force H is within the above range, it is possible to impart a shape retaining property capable of properly maintaining the bend shape to the lead wire for electric parts. As a result, the bending operation of the lead wire for electrical parts becomes easier, and workability is further improved.

The average thickness of the strip-shaped conductor is preferably 30 μm or more and 200 μm or less, and the elastic modulus of the strip-shaped conductor is preferably 50 MPa or more and 300 MPa or less. According to such a lead wire, it is possible to make the shape-retaining force of the strip-shaped conductor into an appropriate range, and to provide the shape-retaining property that can properly maintain a bent shape to the lead wire for electric parts. As a result, the bending operation of the lead wire for electrical parts becomes easier, and workability is further improved.

The average thickness of each insulating film is preferably 25 μm or more and 200 μm or less, and the elastic modulus of each insulating film is preferably 100 MPa or more and 1,400 MPa or less. According to such a lead wire, the elastic recovery force of an insulating film can be made into an appropriate range, and the spring back after bending of the lead wire for electrical parts can be made appropriately small. As a result, the bending work of the lead wire for electrical parts becomes easier, and workability is further improved.

The electric component according to one embodiment of the present invention includes a lead wire for the electric component. Since the electrical component includes a lead wire for the electrical component, the work efficiency can be improved by simplifying the bending of the lead wire for the electrical component and maintaining its shape.

The electrical component may be a non-aqueous electrolyte battery. In this way, the electrical component can be suitably used as a nonaqueous electrolyte battery because of its excellent work efficiency.

[Details of embodiments of the present invention]

A specific example of the lead wire for an electric component and the electric component according to the embodiment of the present invention will be described with reference to the drawings. In addition, the present invention is not limited to these examples, is indicated by the claims, and is intended to include all changes within the meaning and range equivalent to the claims.

<Lead wire for electrical parts>

1 and 2, a lead wire 1 for an electrical component according to an embodiment of the present invention has a strip-shaped conductor 2 and a pair of insulating films covering both sides of the strip-shaped conductor 2 (3) is provided.

(Strip shape conductor)

The strip-shaped conductor 2 is connected to an electrode (positive electrode 5A and negative electrode 5B) of an electric component such as a lithium ion battery 4 or the like. This strip-shaped conductor 2 is formed of a material having high conductivity. Examples of such highly conductive materials include metal materials such as aluminum, titanium, nickel, copper, aluminum alloys, titanium alloys, nickel alloys, copper alloys, and materials plated with nickel, gold, or the like. Can be. As a material for forming the strip-shaped conductor 2 connected to the positive electrode 5A of an electrical component such as a lithium ion battery 4, those that do not dissolve during discharge, specifically aluminum, titanium, aluminum alloy and titanium alloy desirable. On the other hand, nickel, copper, nickel alloy, copper alloy, nickel-plated copper, and gold-plated copper are preferable as the material for forming the strip-shaped conductor 2 connected to the cathode 5B. Further, the strip-shaped conductor 2 may be subjected to surface treatments such as chromate treatment, trivalent chromium treatment, non-chromate treatment, roughening treatment, etc. to improve electrolyte resistance. By such surface treatment, resistance to the electrolytic solution of the strip-shaped conductor 2 can be improved.

When the elastic modulus of the strip-shaped conductor 2 is D _m [㎩] and the secondary moment of section per 1 mm of width is I _m [m ⁴ /1 mm], the strip-shaped conductor (2) represented by the following formula (1) ), the lower limit of the shape holding force H [N·m 2/1 mm] per 1 mm of width is preferably 3.0×10 ^-4 N·m 2 /1 mm, and more preferably 2.0×10 ^-3 N·m 2 /1 mm. Do. The upper limit of the shape holding force H is preferably 6.0 x 10 ^-2 N·m2/1 mm, more preferably 1.0 x 10 ^-2 Nm2/1 mm.

H=D _m ×I _m … (One)

The strip-shaped conductor 2 can give the lead wire 1 for electrical components a shape-retaining property that can properly maintain the bending shape because the shape-holding force H can be more appropriately maintained due to the above range. Can be. As a result, bending of the lead wire 1 for electrical components and maintaining the shape thereof become easier, and workability is further improved.

Here, the cross-sectional secondary moment per 1 mm width of the strip-shaped conductor 2 in the above formula (1) and the cross-sectional moment per 1 mm width of the pair of insulating films 3 in the following formula (2) The calculation method will be described by taking the lead wire 11 for an electric component of Fig. 3A as an example. The lead wire 11 for electrical components shown in Fig. 3(a) has the same average thickness of the pair of insulating films 13 and the same average width. The average thickness of the lead wire 11 for this electrical component is T, the average thickness of the strip-shaped conductor 12 is T _m [m], and the average thickness of each pair of insulating films 13 is T _i [m]. . In addition, the average width of the strip-shaped conductor 12 is W _m [m], and the average width of the pair of insulating films 13 is W _i [m]. In addition, the surface in which the lead wire 11 for an electrical component is bisected in the thickness direction (the surface in which the strip-shaped conductor 12 is bisected in the thickness direction) is regarded as the center plane M of the bending deformation of the lead wire 11 for electrical components. can do.

Next, the cross-sectional moment of the strip-shaped conductor 12 can be calculated by the following equation (5) based on the cross-sectional shape shown in Fig. 3(b). Similarly, the section moment of the pair of insulating films 13 can be calculated by the following formula (6) based on the section shape shown in Fig. 3(c).

2nd section moment of inertia per 1 mm of width of the strip-shaped conductor [m ⁴ /1 mm]=1/12 × average width of the strip-shaped conductor W _m [m] × (average thickness of the strip-shaped conductor T _m [m]) ³ / Average width of strip-shaped conductor W _m [mm]. (5)

Secondary moment of cross section [m ⁴ /1 mm] per 1 mm width of a pair of insulating films=1/12×average width of a pair of insulating films W _i [m]×{(average thickness T of lead wires for electrical parts [m]) ³ -(average thickness of strip-shaped conductor T _m [m]) ³ }/1 average width of pair of insulating films W _i [mm]… (6)

Moreover, when the average thickness or average width of one pair of insulating films 3 of the lead wire 1 for electrical components is not the same, the average value of each average thickness or each average width of one pair of insulating films 3 is calculated|required. , The above-mentioned calculation is performed on the assumption that the average thickness or average width of the pair of insulating films 3 are all the above average values. Then, the shape retention force H and the elastic recovery force R are determined using the cross-sectional secondary moment per 1 mm width of the strip-shaped conductor 2 and the pair of insulating films 3 obtained by this calculation.

As the lower limit of the cross-sectional moment per 1 mm of width of the strip-shaped conductor 2, 5.0 x 10 ^-15 m ⁴ /1 mm is preferable, and 2.0 x 10 ^-14 m ⁴ /1 mm is more preferable. On the other hand, as the upper limit of the cross-sectional moment, 8.0 x 10 ^-13 m ⁴ /1 mm is preferable, and 1.0 x 10 ^-13 m ⁴ /1 mm is more preferable. By setting the said section moment in the said range, the shape holding force H per 1 mm of width of the strip-shaped conductor 2 can be adjusted easily and reliably to the said range.

The average thickness of the strip-shaped conductor 2 is preferably 30 µm or more and 200 µm or less. As the lower limit of the average thickness of the strip-shaped conductor 2, 40 µm is more preferable, and 47 µm is more preferable. On the other hand, as the upper limit of the average thickness of the strip-shaped conductor 2, 150 µm is more preferable, and 120 µm is more preferable. When the average thickness of the strip-shaped conductor 2 is less than the above-mentioned lower limit, there is a fear that the electric resistance value of the lead wire 1 for an electric component increases. Conversely, when the average thickness exceeds the upper limit, there is a fear that the lead wire 1 for an electric component becomes unnecessarily thick, and cannot sufficiently respond to the demand for thickness reduction.

The elastic modulus of the strip-shaped conductor 2 is preferably 50 MPa or more and 300 MPa or less. As a lower limit of the elastic modulus of the strip-shaped conductor 2, 60 MPa is more preferable, and 67 MPa is more preferable. On the other hand, as the upper limit of the elastic modulus of the strip-shaped conductor 2, 250 MPa is more preferable, and 210 MPa is more preferable. When the elastic modulus of the strip-shaped conductor 2 is less than the above lower limit, there is a fear that it is difficult to suppress the springback of the lead wire 1 for electrical parts. Conversely, when the elastic modulus exceeds the upper limit, there is a fear that workability may be deteriorated by requiring force for bending the lead wire 1 for an electric component. In addition, the modulus of elasticity of the strip-shaped conductor 2 can be adjusted by changing its material, and in particular, by using the strip-shaped conductor 2 as an alloy, it is possible to finely adjust the modulus of elasticity by changing the alloy component.

In addition, since the strip-shaped conductor 2 has an average thickness of 30 µm or more and 200 µm or less, and an elastic modulus of 50 µm or more and 300 µm or less, the shape-retaining force H is in a very suitable range, and the lead wire 1 for electrical components is used. To this, it is possible to impart shape retaining properties capable of properly maintaining a bent shape. As a result, the shape fixing operation at the time of bending of the lead wire 1 for electric parts becomes easier, and the workability is further improved.

(1 pair of insulating film)

The pair of insulating films 3 cover both sides of the central portion of the strip-shaped conductor 2 in a state where both ends of the strip-shaped conductor 2 are exposed, such as a lithium ion battery 4 or the like. It is a part fixed to the sealing body 6 of the electric component.

Each insulating film 3 is formed of a resin material having high insulating properties. The resin material is preferably a resin material having high adhesion to the strip-shaped conductor 2 or a resin material that is difficult to melt by heating when the encapsulation body 6 is heat-sealed.

As a resin material with high adhesion to the strip-shaped conductor 2, for example, a thermoplastic polyolefin or the like can be mentioned. Examples of the thermoplastic polyolefin include reactive resins such as polyethylene, acid modified polyethylene, polypropylene, acid-modified polypropylene (for example, maleic anhydride-modified polypropylene), and ionomers, or the like. And mixtures.

On the other hand, as a resin material which is hard to melt by heating when heat-sealing the sealing body 6, cross-linked polyolefin or the like is exemplified. As this crosslinked polyolefin, what crosslinked the polyolefin illustrated above can be used. As a method of crosslinking the polyolefin, crosslinking by irradiation of ionizing radiation such as electron beams or gamma rays, chemical crosslinking with peroxides, silane crosslinking, and the like are used. When crosslinking the polyolefin by ionizing radiation, a cross-linking assistant is added to the polyolefin as needed. As this crosslinking aid, for example, trimethylol propane methacrylate, pentaerythritol triacrylate, ethylene glycol dimethacrylate, and triallyl cyanurate ( triallyl cyanurate, triallyl isocyanurate, etc. are used.

The gel fraction in the crosslinked polyolefin is preferably 20% or more and 90% or less. In addition, the gel fraction is an index indicating the degree of crosslinking, and refers to the proportion of the gel (insoluble polymer chain) in the crosslinked polyolefin that is not dissolved in a solvent such as xylene. When the gel fraction is less than 20%, the degree of crosslinking is insufficient, and there is a fear that the insulating film 3 is melted during heat sealing. Conversely, when the gel fraction exceeds 90%, the degree of crosslinking is too large, and there is a fear that the adhesiveness of the crosslinked polyolefin and the encapsulating body 6 is deteriorated.

Moreover, each insulating film 3 may be a single layer or may be laminated in multiple layers. When the insulating film 3 is constituted as a plurality of layers, the insulating film 3 is formed by heat-sealing the insulating layer formed of a resin material having high adhesion to the strip-shaped conductor 2 and the sealing body 6 It is preferable to include an insulating layer formed of a resin material that is difficult to melt by heating. When the insulating film 3 having such a laminated structure is employed, adhesion to the strip-shaped conductor 2 can be ensured, and melting during heat sealing can be prevented.

When the average modulus of elasticity of one pair of insulating films 3 is D _i [㎩] and the secondary moment of section per 1 mm of width is I _i [m ⁴ /1 mm], one pair represented by the following formula (2) As the lower limit of the elastic recovery force R [N·m 2/1 mm] per 1 mm of the width of the insulating film 3, 3.0×10 ^-5 N·m 2 /1 mm is preferable, and 1.0×10 ^-4 N·m 2 / 1 mm is more preferable. On the other hand, as the upper limit of the elastic recovery force R, 6.0×10 ^-3 N·m 2 /1 mm is preferable, and 1.0×10 ⁻³ N·m 2 /1 mm is more preferable.

R=D _i ×I _i … (2)

When the elastic recovery force per 1 mm of width of the pair of insulating films 3 is within the above range, the spring back after bending of the lead wire 1 for electrical components can be appropriately suppressed. As a result, the operation of bending the lead wire 1 for an electric component and maintaining its shape becomes easier, and the workability is further improved. In addition, the modulus of elasticity of the insulating film 3 can be adjusted by changing the material, and when each insulating film 3 is formed of a crosslinked resin, the modulus of elasticity can also be adjusted by changing the degree of crosslinking.

As the lower limit of the section moment per 1 mm width of the pair of insulating films 3, 1.0 × 10 ^-13 m ⁴ /1 mm is preferable, and 5.0 × 10 ^-13 m ⁴ /1 mm is more preferable. On the other hand, as the upper limit of the cross-sectional moment, 8.0×10 ^-12 m ⁴ /1 mm is preferable, and 1.0×10 ^-12 m ⁴ /1 mm is more preferable. By setting the said cross-sectional moment in the said range, the elastic recovery force per 1 mm of width of the pair of insulating films 3 can be adjusted easily and certainly to the said range.

The average thickness of each insulating film 3 is preferably 25 µm or more and 200 µm or less. As a lower limit of the said average thickness, 40 micrometers is more preferable, and 60 micrometers is more preferable. On the other hand, as the upper limit of the average thickness, 120 µm is more preferable, and 80 µm is more preferable. When the average thickness of each insulating film 3 is less than the above lower limit, the thickness of the insulating film 3 becomes too thin for the thickness of the strip-shaped conductor 2, and as a result, the encapsulation body for the electrical component lead wire 1 When heat-sealed to adhere to (6), there is a fear of shorting between the strip-shaped conductor 2 and the sealing body 6. This short-circuit concern is particularly remarkable at the edge portions (both ends in the width direction) of the strip-shaped conductor 2. Conversely, when the average thickness exceeds the upper limit, there is a fear that the springback of the lead wire 1 for electrical components cannot be sufficiently suppressed.

It is preferable that the average thickness and elastic modulus of each of the insulating films 3 are approximately the same. Specifically, the ratio of the average thickness of the insulating film 3 on the other side to the average thickness of the insulating film 3 on one side (average thickness of the insulating film 3 on the other side/insulating film 3 on the other side) ) Is preferably 0.95 or more and 1.05 or less. The ratio of the modulus of elasticity of the insulating film 3 on the other side to the modulus of elasticity of the insulating film 3 on one side (elastic modulus of the insulating film 3 on the other side/elastic modulus of the insulating film 3 on the other side) is It is preferable that it is 0.7 or more and 1.5 or less.

Further, as the lower limit of the ratio of the average thickness of each insulating film 3 to the average thickness of the strip-shaped conductors 2 (average thickness of the insulating film/average thickness of the strip-shaped conductors), all of 0.2 are preferable, and 0.3 is It is more preferable, and 0.35 is more preferable. On the other hand, as an upper limit of the said ratio, 1.5 is preferable, 1.2 is more preferable, and 1.0 is more preferable. By setting the ratio of the average thickness of each insulating film 3 to the average thickness of the strip-shaped conductors 2 in the above range, the elasticity of the pair of insulating films 3 with respect to the shape-retaining force of the strip-shaped conductors 2 The ratio of the recovery force can be adjusted within an appropriate range, and as a result, it becomes possible to keep the desired bending shape by reducing the spring back angle.

Ratio of the section 2nd moment of inertia per 1mm width of the pair of insulating films 3 to the section 2nd moment of inertia per 1mm width of the strip-shaped conductor 2 (section 2nd per 1mm width of the pair of insulating films) As the lower limit of the moment/strip-shaped conductor per second width of 1 mm of the conductor), 1.0 is preferable, and 3.0 is more preferable. On the other hand, as an upper limit of the said ratio, 4.0x10 is preferable and 2.5x10 is more preferable. By setting the ratio to the above range, the ratio of the elastic recovery force of the pair of insulating films 3 to the shape retaining force of the strip-shaped conductor 2 can be adjusted to an appropriate range, and as a result, the spring back angle is made small, It becomes possible to maintain the desired bending shape.

The elastic modulus of each insulating film 3 is preferably 100 MPa or more and 1,400 MPa or less. As the lower limit of the elastic modulus, 150 MPa is more preferable, and 200 MPa is more preferable. On the other hand, as the upper limit of the elastic modulus, 720 MPa is more preferable, and 350 MPa is more preferable. When the elastic modulus of the insulating film 3 is within the above range, the elastic recovery force of the insulating film 3 can be made appropriate.

In addition, each insulating film 3 has an average thickness of 25 µm or more and 200 µm or less, and an elastic modulus of 100 µm or more and 1,400 µm or less, so that the springback angle after bending of the lead wire 1 for electric parts is appropriately small. can do. As a result, the operation of bending the lead wire 1 for an electric component and maintaining its shape becomes easier, and the workability is further improved.

As the lower limit of the ratio of the average elastic modulus of the pair of insulating films 3 to the elastic modulus of the strip-shaped conductors 2 (average elastic modulus of the pair of insulating films 3/elastic modulus of the strip-shaped conductors 2), 1.0 X 10 ^-3 is preferable, and 2.0 x 10 ^-3 is more preferable. On the other hand, as the upper limit of the ratio, 4.0 × 10 ^-2 it is preferred, more preferably 1.5 × 10 ^-2. By setting the ratio to the above range, the ratio of the elastic recovery force of the pair of insulating films 3 to the shape retaining force of the strip-shaped conductor 2 can be adjusted to an appropriate range, and as a result, the spring back angle is made small, It becomes possible to maintain the desired bending shape.

The ratio of the elastic recovery force R per 1 mm width of the pair of insulating films 3 to the shape holding force H per 1 mm width of the strip-shaped conductor 2 is 0.15 or less in the lead wire 1 for electrical components. As an upper limit of the said ratio, 0.10 is preferable and 0.05 is more preferable. Moreover, although there is no restriction|limiting in particular about the lower limit of the said ratio, 0.001 is preferable and 0.002 is more preferable.

The lead wire 1 for an electrical component preferably has a bending restoration angle (spring back angle) of 180° or less after bending. According to the lead wire 1 for electric parts, by setting the bending restoration angle (spring back angle) after 180° bending to be 20° or less, the bending shape can be more appropriately maintained, making it easier to fix the shape during bending. The workability is improved further. In addition, the smaller the bending recovery angle, the better the smaller, more preferably 12° or less, more preferably 5° or less, and most preferably 0°.

<electric parts>

The electric component according to the embodiment of the present invention includes a lead wire 1 for an electric component. Examples of the electrical components in which the lead wires 1 for electrical components are used include, for example, nonaqueous electrolyte batteries such as lithium ion batteries, capacitors such as lithium ion capacitors, and electric double-layer capacitors (EDLC). have. Of course, the lead wire 1 for an electric component can be applied to all electric components requiring a lead wire, and the same effect can be obtained even when applied to a battery or the like other than a nonaqueous electrolyte battery.

Hereinafter, a non-aqueous electrolyte battery having a lead wire 1 for an electrical component will be described with reference to the drawings taking lithium ion batteries as an example.

(Lithium ion battery)

The lithium-ion battery 4 shown in FIGS. 1 and 2 encapsulates a battery element holding a non-aqueous electrolyte inside the encapsulation body 6. The battery element holds a non-aqueous electrolyte in a state in which a separator (not shown) is interposed between the positive electrode 5A and the negative electrode 5B. As the non-aqueous electrolyte, for example, those in which lithium compounds (LiClO ₄ , LiBF _4, etc.) are dissolved in an organic solvent such as propylene carbonate or γ-butyrolactone are used.

The lead wire 1 for an electrical component is fixed to the sealing body 6 in the insulating film 3. In the lead wire 1 for an electrical component, one end 2A and the other end 2B of the strip-shaped conductor 2 are exposed from the insulating film 3, and the strip-shaped conductor 2 is exposed. While one end 2A is connected to the positive electrode 5A or the negative electrode 5B of the battery element, the other end 2B of the strip-shaped conductor 2 is exposed from the sealing body 6 Is protruding.

Since the lithium ion battery 4 includes a lead wire 1 for electrical components, it is possible to bend the lead wire 1 for electrical components and simplify the work for maintaining its shape, thereby improving work efficiency. Can be.

Further, even when the lead wire 1 for an electric component is applied to an electric component other than the lithium ion battery 4, it is possible to simplify the work for maintaining the bent shape, thereby improving work efficiency.

(Example)

Next, the present invention will be specifically described by experimental examples, but the present invention is not limited by the following experimental examples, and it is also possible to carry out appropriate changes in a range suitable for the purpose of the present invention, and they are all the present invention. It is included in the technical scope of.

In this experimental example, the spring back angle of the lead wire was evaluated.

<Lead ship>

The lead wire was formed by covering a central portion of the strip-shaped conductor with a pair of insulating films so that both ends of the strip-shaped conductor were exposed. 4(a) and 4(b), as the strip-shaped conductor 7, the length L _m is 80 mm, the width W _m is 5 mm, and the elastic modulus and the average thickness T _m are shown in Table 1 below. What was shown was used. As the insulating film 8, the length L _i was 6 mm, the width W _i was 7 mm, and the elastic modulus and the average thickness T _i were used as values shown in Table 1 below. Moreover, the same thing was used for the two insulating films 8. In addition, the total average thickness of the strip-shaped conductor 7 and the pair of insulating films 8 was taken as the average thickness T of the lead wires.

<2nd moment of section>

The secondary moment [m ⁴ /1 mm] in cross section per 1 mm of width of the strip-shaped conductor 7 is 1/12 x W _m [m] x (T _m [m]) ³ /W _m [mm], respectively. It was obtained by substituting. The secondary moment [m ⁴ /1 mm] of the cross section of the pair of insulating films 8 is 1/12×W _i [m]×{(T[m]) ³ -(T _m [m]) ³ }/ It was calculated by substituting each numerical value in W _i [mm].

<Evaluation of spring back angle>

The spring back angle was evaluated as follows. First, as shown in Fig. 5(a), the cross section of the plate X having a thickness of 0.5 mm is brought into contact with the vicinity of the longitudinal center of the insulating film 8 on one side of the lead wire, and the lead wire is slowly rotated 180° to sandwich the plate X. After bending, a load F was applied by installing a weight of 200 g on the other insulating film 8, and this state was maintained for 10 seconds. Next, as shown in Fig. 5(b), it was evaluated by measuring the spring back angle θ [deg] (angle formed by the lead wire) when the load was removed and left for 5 seconds or more. Table 1 shows the measurement results of the spring back angle. 6 shows the relationship between the spring back angle θ and the ratio (R/H) of the elastic recovery force R per 1 mm width of the pair of insulating films to the shape holding force H per 1 mm width of the strip-shaped conductor. In addition, the elastic recovery force R and the shape retention force H of the lead wire were calculated based on the formulas (1) and (2), respectively.

As shown in Table 1 and FIG. 6, Group A (Production Examples 1 to 4), Group B (Production Examples 5 to 8), and Group C having different average conditions of the strip-shaped conductors and changing other conditions. In (Production Examples 9 to 12), in any group, the spring back angle θ also became smaller as the average thickness T1 of the strip-shaped conductor increased, that is, the ratio of the elastic recovery force R to the shape retention force H (R/H) decreased. . In addition, although the thickness T2 of the insulating film is different between the groups A to C, when these groups A to C are compared, the increase in the thickness T2 of the insulating film, that is, the ratio of the elastic recovery force R to the shape retention force H (R/H ), the spring back angle θ also increased. From these results, it is preferable to adjust the average thickness of the strip-shaped conductor of the lead wire and the average thickness of the insulating film, so that the ratio (R/H) to the shape-retaining force H of the elastic recovery force R is 0.15 or less, so that the spring back angle is 20° or less. It is judged that it is possible to maintain the bending restoration shape.

In groups D (manufacturing examples 13 to 14) and group E (manufacturing examples 15 to 16) in which the elastic modulus of the insulating film was changed and other conditions were the same, both groups D and E increased the elastic modulus of the insulating film, that is, As the ratio (R/H) to the shape-retaining force H of the elastic recovery force R increased, the spring back angle θ also increased. From this result, it is possible to maintain a good bending restoring shape such that the springback angle is 20° or less by adjusting the modulus of elasticity of the insulating film of the lead wire and setting the ratio (R/H) of the elastic recovery force R to the shape holding force H of 0.15 or less. Is judged.

In group F (manufacturing examples 17 to 20) in which the thickness of the strip-shaped conductor and the insulating film was made constant and the elastic modulus was changed, the elastic recovery force R was increased by increasing the elastic modulus of the strip-shaped conductor, reducing the elastic modulus of the insulating film, or a combination thereof. When the ratio (R/H) to the shape-retaining force of H was reduced, the springback angle θ was reduced accordingly. From this result, it is possible to maintain a good bending restoring shape such that the springback angle is 20° or less by adjusting the modulus of elasticity of the insulating film of the lead wire and setting the ratio (R/H) of the elastic recovery force R to the shape holding force H of 0.15 or less. Is judged.

In addition, as shown in Fig. 6, the ratio (R/H) to the shape-retaining force H of the elastic recovery force R and the spring back angle show a high correlation, and in particular, the ratio (R/H) is small (for example, 0.2 or less). ) In the preparation example, a higher correlation was exhibited. Therefore, it can be confirmed that in reducing the spring back angle, it is very effective to adjust the ratio (R/H).

1, 11: Lead wire for electrical parts
2, 7, 12: strip-shaped conductor
2A: one end
2B: the other end
3, 8, 13: insulating film
4: Li-ion battery
5A: anode
5B: cathode
6: Encapsulation body
M: Center plane of bending deformation

Claims (8)

A lead wire for an electrical component comprising a strip-shaped conductor and a pair of insulating films covering both sides of the strip-shaped conductor,
The elastic modulus of the strip-shaped conductor is D _m [㎩], the secondary moment of section per mm of width is I _m [m ⁴ /1 mm], and the average elastic modulus of the pair of insulating films is D _i [㎩]. , When the cross-sectional secondary moment per 1 mm of width is set to I _i [m ⁴ /1 mm], the shape retention force per width of 1 mm of the strip-shaped conductor represented by the following formula (1) H [N·㎡/1 mm The ratio (R/H) of the elastic recovery force R [N·m 2/1 mm] per 1 mm of width of the insulating film represented by the following formula (2) for] is 0.15 or less,
The cross-sectional secondary moment per 1 mm width of the strip-shaped conductor and the insulating film is defined by the following equations (5) and (6), respectively.
Lead wire for electrical components.
H=D _m ×I _m … (One)
R=D _i ×I _i … (2)
I _m [m ⁴ /1㎜]=1/12×average width of strip-shaped conductor W _m [m]×(average thickness of strip-shaped conductor T _m [m]) ³ /average width of strip-shaped conductor W _m [ ㎜]… (5)
I _i [m ⁴ /1㎜]=1/12×1 The average width of a pair of insulating films W _i [m]×{(Average thickness of lead wires for electrical components T[m]) ³ -(Average of strip-shaped conductors Thickness T _m [m]) Average width of ³ }/1 pair of insulating films W _i [mm]… (6)
According to claim 1,
Bend recovery angle after 180° bending is 20° or less
Lead wire for electrical components.

The method of claim 1 or 2,
The elastic recovery force R is 3.0×10 ^-5 N·㎡/1㎜ or more and 6.0×10 ^-3 N·㎡/1㎜ or less
Lead wire for electrical components.
The method of claim 1 or 2,
The shape-retaining force H is 3.0×10 ^-4 N·㎡/1㎜ or more and 6.0×10 ^-2 N·㎡/1㎜ or less
Lead wire for electrical components.
The method of claim 1 or 2,
The average thickness of the strip-shaped conductor is 30 μm or more and 200 μm or less,
The elastic modulus of the strip-shaped conductor is 50㎬ or more and 300㎬ or less.
Lead wire for electrical components.
The method of claim 1 or 2,
The average thickness of each of the insulating films is 25 µm or more and 200 µm or less,
The elastic modulus of each insulating film is 100 ㎫ or more and 1,400 ㎫ or less.
Lead wire for electrical components.
An electric component comprising the lead wire for an electric component according to claim 1.
The method of claim 7,
Non-aqueous electrolyte battery
Electrical components.

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