Preparation method and application of copper-nickel alloy foil

Abstract

According to the preparation method and application of the copper-nickel alloy foil, the electrolyte for preparing the copper-nickel alloy foil is supplied between the anode plate and the cathode roller; the electrolyte comprises 100 to 200 parts by mass of nickel sulfate hexahydrate, 2 to 15 parts by mass of nickel chloride hexahydrate, 10 to 60 parts by mass of copper sulfate pentahydrate, 40 to 100 parts by mass of sodium citrate, 40 to 100 parts by mass of boric acid, 2 to 10 parts by mass of saccharin sodium salt and 0.1 to 0.2 part by mass of polyethylene glycol; the concentration of chloride ions in the electrolyte is less than 5g / L; applying voltage between the anode plate and the cathode roller, and electrolyzing the electrolyte to form a copper-nickel alloy foil on the surface of the cathode roller; by means of the mode, the chloride ion concentration in the electrolyte is controlled within a low range, the adding proportion of the metal complexing agent, the acid-base regulator, the brightening agent and the wetting agent is controlled, and the tensile strength and the ductility of the copper-nickel alloy foil can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of alloy foil manufacturing, in particular to a preparation method of copper-nickel alloy foil and application thereof. BACKGROUND

[0002] The copper-nickel alloy foil is an alloy material with good electrical properties, mechanical properties, corrosion resistance and soft magnetic properties, which is widely used in the electronic and electrical industries, especially in the fields of communication, radar, electronic computer, automatic control instrument and the like. With the progress of science and technology, the materials required by many high-tech fields are developing towards lightness and thinness. In recent years, the electrodeposited micron copper-nickel alloy foil has become a research hotspot of battery current collector materials due to its lightness, excellent physical properties and good electrical conductivity. The preparation of copper-nickel alloy foil by electrodeposition has the advantages of isotropy in physical properties, easy thickness control and low production cost, and the research on electrodeposited copper-nickel alloy foil has a very broad application prospect.

[0003] At present, how to improve the tensile strength and elongation of the copper-nickel alloy foil has become a technical problem to be solved in the field. SUMMARY

[0004] Therefore, the present application provides a preparation method of copper-nickel alloy foil and application thereof to solve the technical problem of how to improve the tensile strength and elongation of the copper-nickel alloy foil in the prior art.

[0005] In a first aspect, the present application provides a preparation method of copper-nickel alloy foil, comprising:

[0006] supplying an electrolyte for preparing copper-nickel alloy foil between an anode plate and a cathode roller; wherein the electrolyte for preparing copper-nickel alloy foil comprises 100-200 parts by mass of nickel sulfate hexahydrate, 2-15 parts by mass of nickel chloride hexahydrate, 10-60 parts by mass of copper sulfate pentahydrate, 40-100 parts by mass of sodium citrate, 40-100 parts by mass of boric acid, 2-10 parts by mass of sodium saccharin and 0.1-0.2 parts by mass of polyethylene glycol; the concentration of chloride ions in the electrolyte for preparing copper-nickel alloy foil is less than 5 g / L;

[0007] applying a voltage between the anode plate and the cathode roller to electrolyze the electrolyte for preparing copper-nickel alloy foil, so as to form the copper-nickel alloy foil on the surface of the cathode roller.

[0008] Optionally, the current density applied between the anode plate and the cathode roller during electrolysis is 8-14 A / dm 2 .

[0009] Optionally, the pH value of the electrolyte for preparing copper-nickel alloy foil during electrolysis is 2-5.

[0010] Optionally, the temperature of the electrolyte for preparing the copper-nickel alloy foil is 50-60℃ during electrolysis.

[0011] Optionally, the average roughness of the cathode roller is 0.12-0.17μm.

[0012] Optionally, the rotating speed of the cathode roller is 7.5-8.4m / min during electrolysis.

[0013] Optionally, the cathode roller is a titanium roller and the anode plate is an iridium-plated titanium plate.

[0014] In the second aspect, the embodiments of the present application provide a copper-nickel alloy foil, which is obtained by the above-mentioned method for preparing a copper-nickel alloy foil.

[0015] Optionally, the thickness of the copper-nickel alloy foil is 4.5-6.0μm.

[0016] In the third aspect, the embodiments of the present application provide a lithium ion battery negative electrode material, which comprises the above-mentioned copper-nickel alloy foil.

[0017] The method and application of the copper-nickel alloy foil of the embodiments of the present application supply the electrolyte for preparing the copper-nickel alloy foil between the anode plate and the cathode roller; wherein the electrolyte for preparing the copper-nickel alloy foil comprises 100-200 mass parts of nickel sulfate hexahydrate, 2-15 mass parts of nickel chloride hexahydrate, 10-60 mass parts of copper sulfate pentahydrate, 40-100 mass parts of sodium citrate, 40-100 mass parts of boric acid, 2-10 mass parts of sodium saccharin and 0.1-0.2 mass parts of polyethylene glycol; the concentration of chloride ions in the electrolyte for preparing the copper-nickel alloy foil is less than 5g / L; a voltage is applied between the anode plate and the cathode roller to electrolyze the electrolyte for preparing the copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller; by the above-mentioned method, the concentration of chloride ions in the electrolyte is controlled in a lower range, and the adding proportion of the metal complexing agent, the acid-base regulator, the brightener and the wetting agent is controlled, which is beneficial to improve the tensile strength and elongation of the copper-nickel alloy foil. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 The flow chart of the method for preparing the copper-nickel alloy foil of the embodiments of the present application. DETAILED DESCRIPTION

[0019] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the related drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0020] It is to be understood that where an element such as a layer, region or substrate is described as being "on" another element, it can be directly on the other element or intervening elements can also be present. Where an element is described as being "connected" or "coupled" to another element, it can be directly connected or coupled or intervening elements can be present.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application.

[0022] As shown in Figure 1 A method for preparing a copper-nickel alloy foil according to an embodiment of the present application.

[0023] As shown in Figure 1 The method for preparing a copper-nickel alloy foil comprises the steps of:

[0024] Step S11: providing an electrolyte for preparing a copper-nickel alloy foil.

[0025] The electrolyte for preparing a copper-nickel alloy foil comprises 100-200 parts by mass of nickel sulfate hexahydrate, 2-15 parts by mass of nickel chloride hexahydrate, 10-60 parts by mass of copper sulfate pentahydrate, 40-100 parts by mass of sodium citrate, 40-100 parts by mass of boric acid, 2-10 parts by mass of sodium saccharin, and 0.1-0.2 parts by mass of polyethylene glycol.

[0026] Step S12: supplying the electrolyte for preparing a copper-nickel alloy foil between an anode plate and a cathode roller.

[0027] The concentration of chloride ions in the electrolyte for preparing a copper-nickel alloy foil is less than 5 g / L.

[0028] Step S13: applying a voltage between the anode plate and the cathode roller to electrolyze the electrolyte for preparing a copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0029] In the related art, the concentration of chloride ions in the electrolyte for preparing a copper-nickel alloy foil is generally greater than 10 g / L, for example, the concentration of chloride ions is generally 12-15 g / L. The related art considers that maintaining the concentration of chloride ions in the above range can improve the electrodeposition efficiency to improve the quality of the obtained copper-nickel alloy foil.

[0030] According to the experimental results of the present embodiment, the concentration of chloride ions in the electrolyte is controlled in a lower range (less than 5.0 g / L), which does not reduce the tensile strength and elongation of the copper-nickel alloy foil, and at the same time, can reduce the corrosiveness of the electrolyte, which is conducive to reducing the synthesis difficulty of the copper-nickel alloy foil.

[0031] The nickel sulfate hexahydrate and the nickel chloride hexahydrate are used to provide metal nickel ions in the electrolysis process; and the copper sulfate pentahydrate is used to provide metal copper ions in the electrolysis process.

[0032] The nickel chloride hexahydrate is also used to provide chloride ions in the electrolysis process, and the chloride ions can reduce the valence state of the active sites of the metal nickel and the metal copper to alleviate the electrodeposition polarization. Specifically, the chloride ions as an anodic activator can form a complex CuCl + and NiCl + with the metal ions (copper ions and nickel ions), so that the equilibrium potential of the metal ions (copper ions and nickel ions) moves negatively, and at the same time, the stress of the copper-nickel alloy foil formed by the electrolytic deposition can be eliminated, and the anodic dissolution can be facilitated.

[0033] In the electrolysis process, the nickel ions and the ferrous ions in the electrolyte are deposited on the surface of the cathode roller to form a copper-nickel alloy foil, and the copper-nickel alloy foil is stripped from the cathode roller and enters the subsequent processing process.

[0034] The sodium citrate is a metal complex, which is used to complex with the metal ions (copper ions and nickel ions) in the electrolysis process to enable the nickel ions and the copper ions to be electrodeposited. Specifically, the molecular structure of the sodium citrate contains multiple carboxyl (-COO - ) and hydroxyl (-OH) functional groups, which can undergo coordination reactions with the metal ions to form stable complexes. For example, the oxygen atoms in the carboxyl groups and the oxygen atoms in the hydroxyl groups can act as coordination atoms to form coordination bonds with the metal ions (Cu 2+ and Ni 2+ ).

[0035] The boric acid is an acid-base regulator, which is used to control the acidic environment in the electrolysis process. Specifically, the boric acid is a monobasic weak acid, which dissociates in water to generate hydrogen ions (H + ) and borate ions (BO3 3- ), so as to adjust the pH value of the electrolyte in the electrolysis process.

[0036] sodium saccharin is a brightener, and the sodium saccharin can be adsorbed on the surface of the cathode (i.e. the copper-nickel alloy foil) to inhibit the rapid and disordered deposition of metal ions and promote the uniform formation of crystal nucleus, thereby refining the grains of the plated layer and making the surface more compact and smooth. Specifically, the sulfonamide group and carboxyl group and other functional groups in the sodium saccharin molecule can be adsorbed on the surface of the alloy foil to form a uniform film, which can improve the microstructure of the surface of the alloy foil and reduce surface defects, thereby improving the brightness of the alloy foil; during the electrolysis process, the sodium saccharin can also inhibit the abnormal deposition of metal ions (Cu 2+ and Ni 2+ ) and prevent the formation of dendrites, thereby improving the brightness of the alloy foil; and the sodium saccharin can refine the grains on the surface of the platinum-gold foil, making the alloy foil more compact and flat. The refinement of the grains can not only improve the brightness of the surface of the alloy foil, but also enhance the hardness and wear resistance of the alloy foil.

[0037] In the present embodiment, the concentration of chloride ions, the concentration of nickel ions and the concentration ratio of copper ions in the electrolyte are controlled, and the addition ratio of the metal complexing agent, the acid-base regulator, the brightener and the wetting agent is controlled, which is conducive to improving the tensile strength and elongation of the copper-nickel alloy foil.

[0038] In the present embodiment, the concentration of chloride ions, the concentration of nickel ions and the concentration ratio of copper ions in the electrolyte are controlled, and the addition ratio of the metal complexing agent, the acid-base regulator, the brightener and the wetting agent is controlled, which is conducive to improving the tensile strength and elongation of the copper-nickel alloy foil.

[0039] As an embodiment, the current density applied between the anode plate and the cathode roller during electrolysis is 8-14 A / dm 2 .

[0040] In the present embodiment, a relatively low current density is used for electrolysis, and the deposition is relatively slow, which allows the grains to grow fully and the structure to be uniform and compact. In addition, the use of a relatively low current density in combination with the dosage control of the brightener can not only allow the grains to grow fully to form a uniform and compact structure, but also alleviate the problem of increased surface roughness of the gold foil caused by low current density, so that the surface roughness of the alloy foil is within a reasonable range.

[0041] As an embodiment, the pH value of the electrolyte used for preparing the copper-nickel alloy foil during electrolysis is 2-5.

[0042] In the present embodiment, the use of boric acid can keep the pH value of the electrolyte within the above range during the electrolysis process.

[0043] As an embodiment, the temperature of the electrolyte used for preparing the copper-nickel alloy foil during electrolysis is 50-60°C.

[0044] In the embodiment, the electrolysis temperature is controlled in the above range, which is beneficial to increase the alloy foil coating compactness while ensuring the deposition rate.

[0045] As an embodiment, the average roughness of the cathode roller is 0.12-0.17 μm.

[0046] In the embodiment, the roughness of the cathode roller is controlled in the above range, which is beneficial to the formation of the crystal phase structure of the alloy foil obtained by electrolysis at the first 0-1.5 μm thickness.

[0047] As an embodiment, the rotating speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0048] As an embodiment, the cathode roller is a titanium roller, and the anode plate is an iridium-plated titanium plate.

[0049] The embodiment provides a copper-nickel alloy foil obtained by the above method.

[0050] As an embodiment, the thickness of the copper-nickel alloy foil is 4.5-6.0 μm.

[0051] The embodiment provides a lithium ion battery negative electrode material comprising the above copper-nickel alloy foil.

[0052] Embodiment 1

[0053] The embodiment provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0054] Step 1: providing the above electrolyte for preparing a copper-nickel alloy foil.

[0055] Table 1: content table of each component in embodiment 1

[0056]

[0057] The content of each component in the electrolyte for preparing a copper-nickel alloy foil is shown in Table 1.

[0058] Step 2: supplying the above electrolyte for preparing a copper-nickel alloy foil between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, and electrolyzing the electrolyte for preparing a copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0059] The current density applied between the anode plate and the cathode roller during electrolysis is 8 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the rotating speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0060] Embodiment 2

[0061] The present embodiment provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0062] Step 1: providing the electrolyte for preparing a copper-nickel alloy foil as described above.

[0063] Table 2: Content table of each component of Example 2

[0064]

[0065] The content of each component of the electrolyte for preparing a copper-nickel alloy foil is shown in Table 2.

[0066] Step 2: supplying the electrolyte for preparing a copper-nickel alloy foil as described above between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, electrolyzing the electrolyte for preparing a copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0067] The current density applied between the anode plate and the cathode roller during electrolysis is 8 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0068] Example 3

[0069] The present embodiment provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0070] Step 1: providing the electrolyte for preparing a copper-nickel alloy foil as described above.

[0071] Table 3: Content table of each component of Example 3

[0072]

[0073] The content of each component of the electrolyte for preparing a copper-nickel alloy foil is shown in Table 3.

[0074] Step 2: supplying the electrolyte for preparing a copper-nickel alloy foil as described above between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, electrolyzing the electrolyte for preparing a copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0075] The current density applied between the anode plate and the cathode roller during electrolysis is 10 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0076] Example 4

[0077] The present embodiment provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0078] Step 1: providing the electrolyte for preparing the copper-nickel alloy foil as described above.

[0079] Table 4: Content table of each component of Example 4

[0080]

[0081] The content of each component of the electrolyte for preparing the copper-nickel alloy foil is shown in Table 4.

[0082] Step 2: supplying the electrolyte for preparing the copper-nickel alloy foil as described above between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, and electrolyzing the electrolyte for preparing the copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0083] The current density applied between the anode plate and the cathode roller during electrolysis is 10 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the rotation speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0084] Example 5

[0085] The present example provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0086] Step 1: providing the electrolyte for preparing the copper-nickel alloy foil as described above.

[0087] Table 5: Content table of each component of Example 5

[0088]

[0089] The content of each component of the electrolyte for preparing the copper-nickel alloy foil is shown in Table 5.

[0090] Step 2: supplying the electrolyte for preparing the copper-nickel alloy foil as described above between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, and electrolyzing the electrolyte for preparing the copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0091] The current density applied between the anode plate and the cathode roller during electrolysis is 12 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the rotation speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0092] Example 6

[0093] The present example provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0094] Step 1: providing the electrolyte for preparing the copper-nickel alloy foil as described above.

[0095] Table 6: content table of each component of Example 6

[0096]

[0097] The content of each component of the electrolyte for preparing the copper-nickel alloy foil is shown in Table 6.

[0098] Step 2: supplying the electrolyte for preparing the copper-nickel alloy foil as described above between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, and electrolyzing the electrolyte for preparing the copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0099] The current density applied between the anode plate and the cathode roller during electrolysis is 12 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the rotation speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0100] Example 7

[0101] The present example provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0102] Step 1: providing the electrolyte for preparing the copper-nickel alloy foil as described above.

[0103] Table 7: content table of each component of Example 7

[0104]

[0105] The content of each component of the electrolyte for preparing the copper-nickel alloy foil is shown in Table 7.

[0106] Step 2: supplying the electrolyte for preparing the copper-nickel alloy foil as described above between the anode plate and the cathode roller, and applying a voltage between the anode plate and the cathode roller, and electrolyzing the electrolyte for preparing the copper-nickel alloy foil to form the copper-nickel alloy foil on the surface of the cathode roller.

[0107] The current density applied between the anode plate and the cathode roller during electrolysis is 14 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the rotation speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0108] Example 8

[0109] The present example provides a method for preparing a copper-nickel alloy foil, comprising the steps of:

[0110] Step 1: providing the electrolyte for preparing the copper-nickel alloy foil as described above.

[0111] Table 8: Content of each component in Example 8

[0112]

[0113] The content of each component in the electrolyte for preparing the copper-nickel alloy foil is shown in Table 8.

[0114] Step 2: The electrolyte for preparing the copper-nickel alloy foil described above is supplied between the anode plate and the cathode roller, and a voltage is applied between the anode plate and the cathode roller, and the electrolyte for preparing the copper-nickel alloy foil is electrolyzed to form the copper-nickel alloy foil on the surface of the cathode roller.

[0115] The current density applied between the anode plate and the cathode roller during electrolysis is 14 A / dm 2 , the electrolysis temperature is 55°C, the pH value during electrolysis is 3, and the rotating speed of the cathode roller during electrolysis is 7.5-8.4 m / min.

[0116] The thickness of the copper-nickel alloy foil prepared in Examples 1-8 is 6 μm, and the experimental results of Examples 1-8 are shown in Table 9.

[0117] Table 9: Experimental results of Examples 1-8

[0118]

[0119] As shown in Table 9, the tensile strength of the nickel-iron alloy foil can reach 1440 MPa or more, and the elongation of the nickel-iron alloy foil can reach 3.2% or more.

[0120] The technical features of the above examples can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above examples are not described, however, as long as the combinations of the technical features do not contradict, they should be considered as within the scope of the present disclosure.

[0121] The above examples only express the preferred embodiments of the present application, and the description is more specific and detailed, but it should not be construed as limiting the scope of the patent application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of the patent application of the present application should be subject to the appended claims.

Claims

1. A method for preparing a copper-nickel alloy foil, characterized in that: include: An electrolyte for preparing a copper-nickel alloy foil is supplied between the anode plate and the cathode roller; wherein the electrolyte for preparing the copper-nickel alloy foil comprises 100-200 parts by mass of nickel sulfate hexahydrate, 2-15 parts by mass of nickel chloride hexahydrate, 10-60 parts by mass of copper sulfate pentahydrate, 40-100 parts by mass of sodium citrate, 40-100 parts by mass of boric acid, 2-10 parts by mass of sodium saccharin, and 0.1-0.2 parts by mass of polyethylene glycol; and the concentration of chloride ions in the electrolyte for preparing the copper-nickel alloy foil is less than 5 g / L; A voltage is applied between the anode plate and the cathode roller to electrolyze the electrolyte for preparing the copper-nickel alloy foil, so as to form the copper-nickel alloy foil on the surface of the cathode roller.

2. The method for preparing the copper-nickel alloy foil according to claim 1, wherein: The current density applied between the anode plate and the cathode roller during electrolysis is 8 to 14 A / dm 2 .

3. The method for preparing the copper-nickel alloy foil according to claim 1, wherein: During electrolysis, the pH value of the electrolyte used to prepare the copper-nickel alloy foil is 2-5.

4. The method for preparing the copper-nickel alloy foil according to claim 1, wherein: The temperature of the electrolyte used to prepare the copper-nickel alloy foil during electrolysis is 50° C. to 60° C.

5. The method for preparing the copper-nickel alloy foil according to claim 1, wherein: The average roughness of the cathode roller is 0.12-0.17 μm.

6. The method for preparing the copper-nickel alloy foil according to claim 1, wherein: During electrolysis, the rotation speed of the cathode roller is 7.5-8.4 m / min.

7. The method for preparing the copper-nickel alloy foil according to claim 1, wherein: The cathode roller is a titanium roller, and the anode plate is an iridium-plated titanium plate.

8. A copper-nickel alloy foil, characterized in that The copper-nickel alloy foil is obtained according to the method for preparing the copper-nickel alloy foil according to any one of claims 1 to 7.

9. The copper-nickel alloy foil according to claim 8, characterized in that The copper-nickel alloy foil has a thickness of 4.5 μm to 6.0 μm.

10. A lithium ion battery negative electrode material, characterized in that: The copper-nickel alloy foil according to claim 8 or 9 is included.

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