Alloy electrolytic foil

Abstract

To provide a metal foil that combines higher corrosion resistance, thinness, and folding resistance. [Solution] An alloy electrolytic foil made of an iron and nickel-based alloy, characterized in that it contains manganese at a content of 30 ppm to 500 ppm by weight and has a thickness of 1.5 μm to 10.0 μm.

Description

[Technical Field]

[0001] This invention relates to an alloy electrolytic foil that is particularly suitable for use as a material for secondary batteries and wiring boards. [Background technology]

[0002] Conventionally, rolled foils and electrolytic foils made from various metal materials have been known for use as current collectors for batteries and materials for wiring boards.

[0003] For example, Patent Document 1 discloses a laminated resin wiring board using an Fe-Ni rolled alloy as the core material. Patent Document 2 also discloses a rolled Fe-Cr-Ni alloy foil for use as a resistor in a multilayer substrate, having a predetermined chemical composition.

[0004] Furthermore, Patent Document 3 discloses an Fe-Ni alloy electrolytic foil used as a material for current collectors in secondary batteries. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2004-031731 [Patent Document 2] Japanese Patent Publication No. 2004-225076 [Patent Document 3] International release 2021 / 075253 [Overview of the project] [Problems that the invention aims to solve]

[0006] For a metal foil used as a current collector of a secondary battery, it has been required to achieve both thinness and strength in order to realize a higher capacity of the battery. As a general strength, tensile strength, which is the difficulty of deformation of the current collector accompanying the expansion and contraction of the active material, has been required. On the other hand, even if the current collector has a tensile strength that does not deform or has a tensile strength that allows deformation without breaking, repeated stress is applied to the current collector due to the expansion and contraction of the active material. In particular, in the case of a secondary battery using a high-capacity active material, which is a more severe battery environment, the expansion and contraction of the active material becomes particularly large. The present inventors focused on this repeatedly applied stress and the fatigue caused thereby as the performance required for the current collector against the expansion and contraction of the active material, and found that the conventional materials have insufficient fold resistance against the deterioration due to this fatigue.

[0007] In addition, with the miniaturization of electronic devices and the like, miniaturization and high density have also been required for wiring boards and the like mounted on these devices. In order to increase the density of wiring boards and the like, it is necessary to fold and accommodate them in an electronic device, and bent portions are often provided. Thus, in order to prevent disconnection due to repeated bending, high fold resistance of the metal foil used as a wiring board is required.

[0008] The present invention has been made in view of solving such problems, and an object thereof is to provide a metal foil having both thinness, tensile strength, and fold resistance.

Means for Solving the Problems

[0009] In order to solve the above-described problems, an alloy electrolytic foil in an embodiment of the present invention is an alloy electrolytic foil made of an alloy based on iron and nickel, containing manganese at a content of 30 weight ppm to 500 weight ppm, and having a thickness of 1.5 μm to 10.0 μm. Further, in the above (1), (2) further contains sulfur at a content of 10 weight ppm or more, and the ratio (R Mn / S ) of the content of manganese and the content of sulfur in the alloy electrolytic foil is preferably 0.2 or more. Also, in the above (1) or (2), at (3) wt%, the ratio (R Ni / Fe ) of the nickel content to the iron content in the alloy electrolytic foil is preferably 0.6 to 10.0. Furthermore, in any one of the above (1) to (3), (4) the iron content is preferably 1.3 g / m 2 to 60.0 g / m 2 . Furthermore, in any one of the above (1) to (4), (5) the nickel content is preferably 5.0 g / m 2 to 81.0 g / m 2 . Furthermore, in any one of the above (2) to (5), (6) the ratio (R Mn / S ) of the manganese content to the sulfur content is preferably 0.4 or more. In any one of the above (3) to (6), (7) the ratio (R Ni / Fe ) of the nickel content to the iron content is preferably 1.0 to 5.0. In any one of the above (1) to (7), (8) the total content ratio of iron and nickel in the alloy electrolytic foil is preferably 90 wt% or more. In order to solve the above problems, a current collector for a battery in one embodiment of the present invention is characterized by being made of the alloy electrolytic foil described in any one of the above (1) to (8).

Effects of the Invention

[0010] According to the present invention, it is possible to provide a metal foil having both thinness and tensile strength and also having fold resistance.

Brief Description of the Drawings

[0011] [Figure 1] It is a schematic diagram of one embodiment of the alloy electrolytic foil of the present invention. [Figure 2] It is a schematic diagram of a test piece used in the tensile test of the example.

Modes for Carrying Out the Invention

[0012] ≪Alloy electrolytic foil≫ The following describes embodiments for implementing the alloy electrolytic foil of the present invention. Figure 1 is a schematic diagram showing one embodiment of the alloy electrolytic foil 10 of the present invention. The alloy electrolytic foil 10 of this embodiment is formed by electroplating. Specifically, the alloy electrolytic foil 10 can be formed using an alloy plating bath.

[0013] The alloy electrolytic foil 10 of this embodiment is an electrolytic foil made of an alloy containing iron (Fe), nickel (Ni), and manganese (Mn).

[0014] In this embodiment, the alloy electrolytic foil 10 includes an alloy based on iron and nickel. Hereinafter, the alloy based on iron and nickel will also be referred to as "iron-nickel alloy" or "Fe-Ni alloy". The state of this iron-nickel alloy may be a solid solution, eutectoid / eutectic, or compound (intermetallic compound), or all of these may coexist. By including an alloy based on iron and nickel, the alloy electrolytic foil 10 can have strength even when thin, while also possessing corrosion resistance.

[0015] The alloy electrolytic foil 10 of this embodiment is characterized by containing manganese (Mn) in a content of 30 ppm to 500 ppm by weight in order to improve its folding resistance. This is preferable because setting the manganese content within the above range greatly contributes to the improvement in folding resistance described later. More preferably, it is 80 ppm to 500 ppm by weight, and even more preferably, 250 ppm to 500 ppm by weight. In this invention, inductively coupled plasma mass spectrometry (ICP-MS) was used as a method for measuring the manganese content in the alloy electrolytic foil 10, but it is not limited to this, and other measurement methods include ICP emission spectrometry and glow discharge mass spectrometry (GD-MS).

[0016] The fold resistance required for the alloy electrolytic foil 10 of the present embodiment will be described below. When the alloy electrolytic foil 10 is used as a current collector, it is important to suppress repeated stress and deterioration due to fatigue caused by the expansion and contraction of the active material in the current collector. In particular, in the case of a secondary battery using a high-capacity active material under more severe battery conditions, the expansion and contraction of the active material becomes particularly large. Therefore, due to the repeated stress associated with this expansion and contraction, fatigue accumulation and load on the current collector increase, and there is a possibility of foil breakage.

[0017] Here, the MIT test is known as a method for evaluating the folding strength until breakage by repeatedly folding paper. The inventors of the present application focused on the fact that the fatigue caused by repeated stress in the above battery can be simulated and reproduced by the MIT test, and applied it as a fold resistance evaluation. And it was found that even in materials having the same tensile strength and elongation, the alloy electrolytic foil 10 of the present embodiment shows superiority or inferiority from the viewpoint of fold resistance. The alloy electrolytic foil 10 of the present embodiment has excellent fold resistance, so that deterioration due to fatigue can be suppressed.

[0018] In general, the MIT test is used to evaluate the strength against bending of paper, thin films, etc. and the durability when repeated stress is applied in accordance with JIS P 8115:2001 standard MIT test. In the alloy electrolytic foil 10 of the present embodiment, it is possible to confirm whether or not the required fold resistance is provided by performing the fold resistance evaluation by this MIT test.

[0019] In particular, when used as a current collector for a battery as described above, higher fold resistance is required. Therefore, among the measurement conditions of the MIT test, it is preferable that the number of folding cycles is 400 or more under the following particularly strict measurement conditions. Here, the number of folding cycles refers to the number of reciprocating bending cycles until the test piece breaks. <MIT test measurement conditions> Test speed: 175 cpm Folding angle: 135° Load: 0.1 kgf Tip R of chuck: 0.38 mm The test specimen size was 15 x 100 mm for evaluation of its bending resistance. By confirming the number of bending cycles under the rigorous measurement conditions described above, it is possible to identify materials with superior bending resistance that can withstand even harsher battery environments.

[0020] In the alloy electrolytic foil 10 of this embodiment, it is preferable that the number of folding cycles is 400 or more, and more preferably 500 or more, and particularly preferably 600 or more, in order to have better folding resistance against repeated stress caused by the expansion and contraction of the active material.

[0021] In alloys such as iron-nickel alloys produced by electroplating, when the iron content is 25 wt% and the nickel content is 75 wt%, the equilibrium phase diagram suggests a ordered structure based on an A3B type (e.g., L12 type) Ni3Fe intermetallic compound. Furthermore, the Ni3Fe phase exhibits the characteristic of having a compositional range in addition to a stoichiometric composition. In the case of 50 wt% iron and 50 wt% nickel, although it does not appear as a phase on the equilibrium phase diagram due to its extremely low diffusion coefficient, it is thought to adopt an ordered structure based on an AB type L10 type FeNi intermetallic compound. Therefore, the scope of this study is presumed to be single phases of Ni3Fe or FeNi, or composite states thereof. These intermetallic compounds are thought to contain periodic stress fields within their structure due to the differences in the atomic radii of their constituent atoms. Furthermore, when the composition deviates from the stoichiometric composition, point defects such as atomic substitutions and vacancies occur in disordered positions, resulting in even greater strain within the metallic structure. The addition of manganese is thought to promote the relaxation of the contained stress field and stabilize the crystal structure by causing the placement of atoms in strongly distorted vacancy positions or substitution with iron or nickel. In other words, it is inferred that the fracture resistance improves due to structural stabilization.

[0022] The alloy electrolytic foil 10 of this embodiment may contain other metal elements and inevitable impurities as long as it can solve the problems of the present invention. For example, it may contain metal elements such as cobalt (Co) and molybdenum (Mo), and additive elements such as boron (B). The proportion of metal elements other than iron, nickel, and manganese in the alloy electrolytic foil 10 is preferably 10% by weight or less in total.

[0023] In other words, it is preferable that the total content rate of iron and nickel in the alloy electrolytic foil 10 of this embodiment is 90% by weight or more. The reason for this is to satisfy the strength and corrosion resistance when the alloy electrolytic foil 10 is used as a current collector material for secondary batteries. More preferably, it is 95% by weight or more, and still more preferably, it is 99% by weight or more. The total content rate of iron and nickel here refers to the total content (g / m 2 ) measured using ICP emission spectrometry measurement described later, etc., and the total content rate of iron and nickel is calculated by dividing the total content by the weight of the alloy electrolytic foil 10.

[0024] Since the alloy electrolytic foil 10 may be substantially an alloy composed only of iron, nickel, and manganese, the lower limit of the content ratio of other metal elements excluding inevitable impurities is 0% by weight. The types and amounts of other metal elements contained can be determined by performing the ICP emission spectrometry measurement described above, but it is not limited to this method, and it can be measured by known means such as a fluorescence X-ray (XRF) measurement device and GDS (glow discharge optical emission surface analysis method).

[0025] In the alloy electrolytic foil 10 in this embodiment, when the total content (by weight) of the metal components of iron and nickel contained in the alloy electrolytic foil 10 is set to 100%, the proportion of iron is preferably 10% to 60% by weight. On the other hand, the content rate of nickel is preferably 40% to 90% by weight.

[0026] Furthermore, when the total content (by weight) of iron and nickel metal components contained in the alloy electrolytic foil 10 is taken as 100%, the proportion of iron is more preferably 25% to 60% by weight, and particularly preferably 25% to 50% by weight. On the other hand, the nickel content contained in the alloy electrolytic foil 10 is more preferably 40% to 75% by weight, and particularly preferably 50% to 75% by weight.

[0027] Controlling the proportion of iron within the above range is preferable from the viewpoint of plating stress during manufacturing and fracture resistance. On the other hand, controlling the proportion of nickel within the above range is preferable from the viewpoint of corrosion resistance and tensile strength obtained. The above method for calculating the ratio of iron to nickel can be determined using ICP emission spectroscopy, which will be described later, but it is not limited to this method, and other known measurement methods can also be used.

[0028] In the alloy electrolytic foil 10 of this embodiment, the ratio of the nickel content to the iron content in the alloy electrolytic foil 10 is (R Ni / Fe It is preferable that the ratio (R) is within the range of 0.6 to 10.0 from the viewpoint of corrosion resistance and folding resistance. In order to further improve the folding resistance of the alloy electrolytic foil 10, the ratio of the content (R) Ni / Fe It is preferable that the ratio (R) is more preferably 0.6 to 5.0, even more preferably 0.6 to 3.0, and particularly preferably 1.0 to 2.5. In particular, the ratio (R) Ni / Fe Setting the value to a range of 1.0 to 2.5 is preferable from the viewpoint of further improving the folding resistance of the alloy electrolytic foil 10 and cost. The iron content and nickel content referred to here are determined by measuring the respective amounts of iron and nickel (g / m³) using ICP emission spectroscopy, as described later. 2 The iron content and nickel content were calculated by measuring the iron content and dividing it by the weight of the alloy electrolytic foil 10.

[0029] When the alloy electrolytic foil 10 of this embodiment is used as a current collector material for a secondary battery, it is generally sealed in the battery container by lamination or winding. To suitably control the handling properties and tensile strength during the manufacturing of such batteries, it is preferable to keep the range within the above range. Furthermore, it is used in organic solvent electrolytes containing lithium salts, highly alkaline solutions, etc., and in all-solid-state batteries, sulfur compounds and strong oxides may be used. To provide corrosion resistance to such highly corrosive substances, it is preferable to keep the range within the above range.

[0030] The thickness of the alloy electrolytic foil 10 in this embodiment is 1.5 μm to 10.0 μm. By setting the thickness within this range, the flexibility and other properties required when the alloy electrolytic foil 10 is applied as a current collector or wiring board in a battery can be achieved. Furthermore, when the alloy electrolytic foil 10 is used as a current collector in a secondary battery, it can enable a higher battery capacity.

[0031] If the thickness of the alloy electrolytic foil 10 exceeds 10 μm, it does not align with the design philosophy aimed at increasing capacity through thinning, and furthermore, the cost advantage compared to known rolled foils, etc., is reduced. On the other hand, if the thickness is less than 1.5 μm, it becomes difficult to have sufficient strength against the effects of charging and discharging, and there is a high possibility that tears, rips, wrinkles, etc. will occur during battery manufacturing or handling.

[0032] In this embodiment, the thickness of the alloy electrolytic foil 10 can be the thickness measured with a micrometer.

[0033] In this embodiment, the alloy electrolytic foil 10 has an iron content of 1.3 g / m². 2 ~60.0g / m 2 This is preferable. The reason is that it can impart desirable strength to the thin alloy electrolytic foil 10 having the thickness described later. More preferably 5.0 g / m 2 ~60.0g / m 2 And more preferably 7.5 g / m 2 ~51.0g / m 2It is preferable that the iron content is within the above range. By setting the iron content within the above range, it is possible to suitably control the thickness of the alloy electrolytic foil 10, the proportion of iron, and other parameters within the above range.

[0034] The iron content mentioned above can be determined by dissolving the alloy electrolytic foil 10 and performing ICP emission spectroscopy analysis, but this method is not the only one available, and other known measurement methods can also be used.

[0035] On the other hand, the alloy electrolytic foil 10 in this embodiment has a nickel content of 5.0 g / m². 2 ~81.0g / m 2 This is preferable because it can impart desirable corrosion resistance to the alloy electrolytic foil 10. More preferably, 5.0 g / m 2 ~72.0g / m 2 And more preferably 8.9 g / m 2 ~55.0g / m 2 It is preferable that this is the case. By setting the nickel content within the above range, it is possible to suitably control the thickness of the alloy electrolytic foil 10 and the proportion of nickel within the range described above.

[0036] The nickel content can also be determined by dissolving the alloy electrolytic foil 10 and performing ICP emission spectroscopy analysis, similar to the iron content. However, this method is not the only way to determine the nickel content; other known measurement methods can also be used.

[0037] In this embodiment, the alloy electrolytic foil 10 preferably contains sulfur (S) as an additive element. In this embodiment, it was found that the ratio of sulfur content to manganese content affects the required folding resistance in the alloy electrolytic foil 10. In this invention, glow discharge mass spectrometry (GD-MS) was used as a method to measure the sulfur content in the alloy electrolytic foil 10, but the invention is not limited to this, and other measurement methods such as high-frequency glow discharge surface spectrometry (GDS) can be used.

[0038] In other words, the alloy electrolytic foil 10 of this embodiment preferably contains 10 ppm by weight to 600 ppm by weight of sulfur, and more preferably 30 ppm by weight to 400 ppm by weight, as this can improve its folding resistance. This is because exceeding the upper limit of 600 ppm by weight of sulfur content would not only saturate the effect of improving folding resistance but could also affect the folding resistance obtained by including manganese.

[0039] Furthermore, the ratio of the manganese content to the sulfur content in the alloy electrolytic foil 10 (R Mn / S It is preferable that the ratio (R) is 0.2 or higher. For example, if the manganese content in the alloy electrolytic foil 10 is 40 ppm by weight and the sulfur content is 200 ppm by weight, then the ratio (R) Mn / S ) is calculated to be 0.2.

[0040] Furthermore, the ratio of the manganese content to the sulfur content (R Mn / S In this case, it is more preferable that the ratio (R) is 0.4 or higher, even more preferably 0.7 or higher, and particularly preferably 0.8 or higher, from the viewpoint of the resulting folding resistance. Mn / S The upper limit of the ratio (R) is preferably 5.0. Mn / S By setting the range within the aforementioned range, it is expected that the flexural resistance will be further improved due to the synergistic effect of manganese and sulfur.

[0041] (Tensile strength) In this embodiment, the tensile strength of the alloy electrolytic foil 10 is preferably 720 MPa or higher. If the tensile strength of the alloy electrolytic foil 10 is less than the above value, tearing or ripping of the foil may occur during battery manufacturing, which is undesirable because it reduces handling. Furthermore, when applied to the current collector of a secondary battery, it may not be able to keep up with the volume expansion due to repeated charging and discharging, which may cause ripping, which is also undesirable. The upper limit of the tensile strength of the alloy electrolytic foil 10 is not particularly limited, but it is preferable that it be 2000 MPa or less from the viewpoint of having the elongation described later.

[0042] (stretch) In this embodiment, the elongation of the alloy electrolytic foil 10 is preferably 0.5% to 5.0% from the viewpoint of being able to follow the volume expansion due to repeated charging and discharging when applied to the current collector of a secondary battery. The elongation of the alloy electrolytic foil 10 in this embodiment can be the value measured in accordance with JIS Z2241 (Method for tensile testing of metallic materials).

[0043] Current collector In this embodiment, the current collector may be the alloy electrolytic foil 10 itself. Furthermore, the current collector in this embodiment may further include a metal layer formed on the alloy electrolytic foil 10. Examples of metal materials constituting the metal layer include nickel, chromium, copper, cobalt, iron, etc. Of these, nickel or nickel alloys are particularly preferred due to their excellent corrosion resistance and strength.

[0044] Furthermore, the current collector in this embodiment may have a roughened nickel layer on the outermost surface of any of the surfaces of the alloy electrolytic foil 10. The metal layer described above may be a roughened nickel layer, or a roughened nickel layer may be formed on the metal layer described above. Details regarding the roughened nickel layer are omitted here, as they are described in, for example, our own application (WO2021 / 020338, etc.).

[0045] ≪Method for manufacturing alloy electrolytic foil≫ An example of a method for manufacturing the alloy electrolytic foil 10 of this embodiment is described below. Generally, the alloy electrolytic foil 10 of this embodiment can be manufactured by forming an alloy plating layer on a support and then peeling it off.

[0046] Specifically, the support on which the alloy plating layer will be formed is first subjected to pretreatment such as polishing, wiping, washing with water, degreasing, and pickling. While titanium or stainless steel plates are suitable materials for the support, the invention is not limited to these, and other known metal materials can be used as long as they do not depart from the spirit of the present invention.

[0047] The surface of the support may be polished to achieve a desired surface roughness of the resulting alloy electrolytic foil 10. That is, when forming an alloy plating layer on the support, the surface shape of the support is generally transferred to the support-side surface of the alloy plating layer (also referred to as the "substrate surface"). Furthermore, the shape of the opposite side of the alloy electrolytic foil 10 (also referred to as the "electrolytic surface") is more likely to reflect the surface shape of the support as the thickness of the alloy electrolytic foil 10 decreases. Therefore, polishing the surface of the support is effective in controlling the surface roughness of the alloy electrolytic foil 10 to a desired value.

[0048] The surface of the support can be polished using known methods. Furthermore, there are no particular restrictions on the polishing direction; the support may be polished in a specific direction such as the width direction or the length direction, or it may be polished randomly.

[0049] The pre-treated support can be immersed in an alloy plating bath as illustrated below to form an alloy plating layer on the support. <Example of alloy plating conditions> ·Bath composition Nickel sulfate hexahydrate: 150~250g / L Iron sulfate heptahydrate: 5~100g / L Manganese chloride tetrahydrate: 1-100 g / L Boric acid: 20-50 g / L Sodium citrate (or trisodium citrate) 1-15 g / L Sodium saccharin: 1-10 g / L ·Temperature: 25~95℃ pH: 2-4 • Agitation: Air agitation or jet agitation ·Current density: 5~50A / dm 2

[0050] Regarding the bath temperature mentioned above, temperatures below 25°C are undesirable because they result in significantly higher foil roughness. Furthermore, these temperatures may prevent layer deposition and make it difficult to incorporate manganese into the foil, potentially resulting in insufficient folding resistance. Conversely, temperatures exceeding 95°C are also undesirable because they increase foil roughness and prevent the acquisition of sufficient tensile strength in the resulting layer.

[0051] If the pH of the bath is less than 2, the roughness of the foil will be significantly higher, which is undesirable. Also, the deposition efficiency of the plating will decrease, which is undesirable. On the other hand, if the pH exceeds 4, the roughness of the foil will be higher, which is undesirable. Also, there is a possibility that sludge will be trapped in the resulting layer, which is undesirable.

[0052] Regarding current density, it is 5A / dm 2 If the value is less than 50A / dm, the foil roughness will be too high, which is undesirable. Furthermore, it may reduce production efficiency, which is also undesirable. 2 If the value exceeds this, it may cause discoloration of the plating, which is undesirable.

[0053] In the example of the alloy plating bath composition described above, saccharin sodium (C7H5NO3SNa) is included as a brightener. However, the manufacturing method in this embodiment is not limited to this, and a brightener other than saccharin sodium containing sulfur (S) may be used, or a brightener that does not contain sulfur (S) may be used.

[0054] Additionally, an appropriate amount of pitting prevention agent may be added to the plating bath.

[0055] The alloy electrolytic foil 10 can be obtained by drying and then peeling off the alloy plating layer formed on the support. Before or after peeling from the support, the outermost surface of the alloy electrolytic foil 10 may be subjected to roughening treatment, rust prevention treatment, or the like, within a range that can achieve the objectives of the present invention. Alternatively, known treatments for imparting conductivity, such as a carbon coating, may be applied.

[0056] The surface of the alloy electrolytic foil 10 may be smoothed by methods such as etching or electrolytic polishing to obtain a desired three-dimensional surface property.

[0057] The manufacturing method for the alloy electrolytic foil 10 in this embodiment described above is an example of performing alloy plating using a continuous manufacturing method (for example, a drum type or roll-to-roll type) with a support. However, it is not limited to this, and a batch manufacturing method using cut plates can also be applied, for example.

[0058] Examples The present invention will be described in more detail below with reference to examples. First, the measurement method used in the examples will be described.

[0059] [Method for measuring the content and percentage of iron (Fe) and / or nickel (Ni)] The obtained alloy electrolytic foil was dissolved and subjected to ICP emission spectroscopy (measurement device: Shimadzu Corporation, inductively coupled plasma emission spectrometer ICPE-9000) to measure the content of iron and nickel. The results are shown in Table 1. The iron and nickel ratios shown in Table 1 represent the iron and nickel content (g / m³). 2 This is the ratio to the total amount of iron and nickel. Furthermore, the total content of iron and nickel is the total amount of iron and nickel (g / m³). 2 The total iron and nickel content was calculated by dividing the weight of the alloy electrolytic foil by the total iron and nickel content (R) shown in Table 1. Ni / Fe In this study, the content percentage (by weight) was calculated by dividing the weight of the alloy electrolytic foil by the respective iron and nickel content, and the ratio of iron to nickel content was determined from the resulting content percentage.

[0060] [Method for measuring manganese (Mn) content] The weight of the obtained alloy electrolytic foil was measured in advance, and the alloy electrolytic foil was melted. Next, the manganese content was measured by inductively coupled plasma mass spectrometry (measurement device: Agilent 8900 triple quadrupole ICP-MS, manufactured by Agilent Technologies), and the manganese content (ppm by weight) was calculated by dividing the measured manganese content by the weight of the alloy electrolytic foil measured in advance. The measurement conditions were: measurement mode: quantitative analysis, carrier gas: argon gas. The results are shown in Table 1. Note that the manganese content shown in Table 1 is the manganese content in the alloy electrolytic foil.

[0061] [Method for measuring sulfur (S) content] In the obtained alloy electrolytic foil, the alloy electrolytic foil was fixed to a flat cell, and the intensity of sulfur relative to the ionic intensities of the main constituent elements, iron and nickel, was measured by glow discharge mass spectrometry (measurement device: Nu Instruments Astrum GD-MS). Subsequently, the sulfur content (ppm by weight) was measured using a relative sensitivity coefficient. The measurement conditions were: measurement method: flat cell, measurement range: 10φ, discharge gas type: argon gas. The results are shown in Table 1. The sulfur content shown in Table 1 is the sulfur content in the alloy electrolytic foil.

[0062] [Measurement of tensile strength and elongation] The tensile strength and elongation of the obtained electrolytic foil were measured as follows. Note that elongation here refers to elongation at break. First, metal pieces were cut into strips of 5 × 100 mm size using a cutting machine. Next, tensile tests were performed on these test pieces in accordance with JIS Z 2241, the JIS standard for tensile testing of metallic materials. A schematic diagram of the test piece is shown in Figure 2. The tensile test was conducted using a tensile testing machine (Shimadzu Autograph AGX-V precision universal testing machine). The measurement conditions were room temperature and a tensile speed of 1 mm / min. For measuring elongation, a video-type non-contact extensometer (TRViewX) was used to measure the distance traveled between gauge points, and the elongation was calculated using the following formula. The original distance between gauge points was set to 20 mm. (Displacement between benchmarks) / (Distance between original benchmarks) × 100 The results are shown in Table 2.

[0063] [Measurement of thickness] The thickness of the obtained electrolytic foil was measured using a micrometer. The obtained values ​​are shown in Table 1.

[0064] [Folding resistance evaluation (MIT test)] In accordance with JIS P 8115, the bending strength of alloy electrolytic foil was measured in a 23°C atmosphere. Specifically, using an MIT BE-202 bending strength tester manufactured by Tester Sangyo Co., Ltd., the bending strength was measured at a test speed of 175 cpm, a bending angle of 135°, and a load of 0.1 kgf, and the number of bends until the alloy electrolytic foil broke was determined. The tip radius of the chuck was 0.38 mm, and the size of the test specimen was 15 × 100 mm. The results are shown in Table 2.

[0065] <Example 1> A manganese-containing iron-nickel alloy plating was formed on a support. Specifically, first, a titanium material was used as the support on which the alloy electrolytic foil was formed on its upper surface. The surface of the titanium material was polished so that the surface roughness Ra of the titanium material was as shown in Table 1. This titanium material was subjected to known pretreatments such as pickling with 7 wt% sulfuric acid and washing with water. Next, the pretreated titanium material was impregnated and electrodeposited in the alloy plating bath shown below to form an alloy electrolytic plating layer on the titanium material. Then, after the alloy electrolytic plating layer formed as described above was thoroughly dried, this plating layer was peeled off the titanium material to obtain an alloy electrolytic foil.

[0066] [Alloy plating conditions] ·Bath composition Nickel(II) sulfate hexahydrate: 230g / L Iron(II) sulfate heptahydrate: 20g / L Mn ions: 30 mmol / L Boric acid: 30g / L Sodium saccharin: 5g / L Trisodium citrate: 10g / L ·Temperature: 80℃±5 pH: 2.4 • Stirring: Air stirring ·Current density: 20A / dm 2 The thickness of the obtained alloy electrolytic foil, the iron and nickel content in the alloy electrolytic foil, the ratio of iron to nickel, the tensile strength, elongation, and folding resistance are shown in Tables 1 and 2, respectively. To determine these content levels, the iron and nickel content was measured by dissolving the alloy electrolytic foil from Example 1 and performing ICP emission spectroscopy. The total iron and nickel content in the alloy electrolytic foil was 99.9% by weight or more, while the content of other elements was less than 0.1% by weight. The manganese and sulfur content in the alloy electrolytic foil was 90 ppm by weight for manganese and 65 ppm for sulfur. The manganese content was measured by inductively coupled plasma mass spectrometry, and the sulfur content was measured by glow discharge mass spectrometry.

[0067] <Example 2> The alloy plating conditions were as follows: [Alloy plating conditions] ·Bath composition Nickel(II) sulfate hexahydrate: 235g / L Iron(II) sulfate heptahydrate: 60g / L Mn ions: 30 mmol / L Boric acid: 30g / L Sodium saccharin: 5g / L Trisodium citrate: 10g / L ·Temperature: 80℃±5 pH: 2.4 • Stirring: Air stirring ·Current density: 30A / dm 2 Otherwise, the procedure was the same as in Example 1. The total content of iron and nickel in the alloy electrolytic foil was 99.9% by weight or more, and the content of other elements was less than 0.1% by weight. The results are shown in Tables 1 and 2.

[0068] <Example 3> The procedure was the same as in Example 3, except that the thickness of the alloy electrolytic foil was configured as shown in Table 1. The results are shown in Tables 1 and 2.

[0069] <Example 4> The alloy plating conditions were as follows: [Alloy plating conditions] ·Bath composition Nickel(II) sulfate hexahydrate: 240g / L Iron(II) sulfate heptahydrate: 80g / L Mn ions: 4 mmol / L Boric acid: 30g / L Sodium saccharin: 5g / L Trisodium citrate: 10g / L ·Temperature: 80℃±5 pH: 2.4 • Stirring: Air stirring ·Current density: 30A / dm 2 Otherwise, the procedure was the same as in Example 1. The total content of iron and nickel in the alloy electrolytic foil was 99.9% by weight or more, and the content of other elements was less than 0.1% by weight. The results are shown in Tables 1 and 2.

[0070] <Example 5> The alloy plating conditions for Example 4 were the same as in Example 4, except that the Mn ion concentration was set to 30 mmol / L and the thickness of the alloy electrolytic foil was configured as shown in Table 1. The results are shown in Tables 1 and 2.

[0071] <Example 6> The alloy plating conditions were the same as in Example 4, except that the Mn ion concentration was set to 30 mmol / L. The results are shown in Tables 1 and 2.

[0072] <Example 7> The procedure was the same as in Example 4, except that the alloy plating conditions were set to Mn ions: 30 mmol / L and the thickness of the alloy electrolytic foil was configured as shown in Table 1. The results are shown in Tables 1 and 2.

[0073] <Example 8> The alloy plating conditions for Example 4 were the same as in Example 4, except that the Mn ion concentration was set to 52 mmol / L. The results are shown in Tables 1 and 2.

[0074] <Example 9> In the alloy plating conditions of Example 4, the Mn ion concentration was set to 98 mmol / L, and the current density was set to 20 A / dm². 2 Except for the points mentioned above, the procedure was the same as in Example 4. The results are shown in Tables 1 and 2.

[0075] <Example 10> The alloy plating conditions for Example 4 were the same as in Example 4, except that the Mn ion concentration was set to 30 mmol / L and the surface roughness Ra of the titanium material was set to the value shown in Table 1. The results are shown in Tables 1 and 2.

[0076] <Example 11> The alloy plating conditions for Example 4 were the same as in Example 4, except that the Mn ion concentration was set to 52 mmol / L and the surface roughness Ra of the titanium material was set to the value shown in Table 1. The results are shown in Tables 1 and 2.

[0077] <Comparative Example 1> The alloy plating conditions were as follows: [Alloy plating conditions] ·Bath composition Nickel(II) sulfate hexahydrate: 230g / L Iron(II) sulfate heptahydrate: 20g / L Nickel(II) chloride hexahydrate: 45 g / L Boric acid: 30g / L Sodium saccharin: 5g / L Trisodium citrate: 10g / L ·Temperature: 60℃±5 pH: 2.4 • Stirring: Air stirring ·Current density: 20A / dm 2 Otherwise, the procedure was the same as in Example 1. The results are shown in Tables 1 and 2.

[0078] <Comparative Example 2> The alloy plating conditions were set to nickel(II) sulfate hexahydrate: 200 g / L, iron(II) sulfate heptahydrate: 50 g / L, and the current density was 30 A / dm². 2 Except for the points mentioned above, the procedure was the same as in Comparative Example 1. The results are shown in Tables 1 and 2.

[0079] <Comparative Example 3> The procedure was the same as in Comparative Example 2, except that the surface roughness Ra of the titanium material was set to the value in Table 1, and the thickness of the alloy electroplating layer was set to the configuration shown in the table. The results are shown in Tables 1 and 2.

[0080] [Table 1]

[0081] [Table 2]

[0082] The above examples and comparative examples demonstrate that by incorporating manganese into the alloy electrolytic foil made of an iron-nickel-based alloy produced by this embodiment, high fold resistance can be obtained even with a thin profile.

[0083] On the other hand, the comparative example, an iron-nickel alloy electrolytic foil that does not contain manganese, was shown to be unable to obtain the required folding resistance within the same thickness range as the above example. [Industrial applicability]

[0084] The alloy electrolytic foil of the present invention can be applied to a wide range of industries, including automobiles and electronic equipment, in addition to being used as a current collector material for secondary batteries. [Explanation of symbols]

[0085] 10 Alloy electrolytic foil

Claims

1. An alloy electrolytic foil made of an iron and nickel-based alloy, It contains manganese at a concentration of 30 ppm by weight to 500 ppm by weight. An alloy electrolytic foil characterized by having a thickness of 1.5 μm to 10.0 μm.

2. Furthermore, it contains sulfur at a concentration of 10 ppm by weight or more, The ratio of the manganese content to the sulfur content in the alloy electrolytic foil (R Ｍｎ／Ｓ The alloy electrolytic foil according to claim 1, wherein the ratio is 0.2 or more.

3. In weight percent, the ratio of the nickel content to the iron content in the alloy electrolytic foil (R Ｎｉ／Ｆｅ The alloy electrolytic foil according to claim 1 or 2, wherein the ratio is 0.6 to 10.

0.

4. The aforementioned iron content is 1.3 g / m ２ ~60.0 g / m ２ The electrolytic foil according to any one of claims 1 to 3.

5. The nickel content is 5.0 g / m ２ ~81.0 g / m ２ The electrolytic foil according to any one of claims 1 to 4.

6. The ratio (R) of the manganese content to the sulfur content Ｍｎ／Ｓ The alloy electrolytic foil according to claim 2, wherein the ratio is 0.4 or more.

7. The ratio of the nickel content to the iron content (R Ｎｉ／Ｆｅ The alloy electrolytic foil according to claim 3, wherein the coefficient of the coefficient is 1.0 to 5.

0.

8. The alloy electrolytic foil according to any one of claims 1 to 7, wherein the total content of iron and nickel in the alloy electrolytic foil is 90% by weight or more.

9. A current collector for a battery, comprising an alloy electrolytic foil as described in any one of claims 1 to 8.

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