Continuous production device and method for ultrathin electrolytic copper-nickel alloy foil

Abstract

The invention discloses a continuous production device and method for ultrathin electrolytic copper-nickel alloy foil. The device comprises a liquid storage tank, an activated carbon filter, a sedimentation tank, a self-circulation pump, a copper-nickel adding tank, a copper-nickel adding pump, a liquid feeding pump, a diatomite filter, a clean liquid tank, an additive tank, an additive pump, a liquid inlet pump and a crude foil machine. The liquid storage tank, the activated carbon filter, the sedimentation tank and the self-circulation pump are sequentially connected, and the liquid storage tank, the sedimentation tank and the activated carbon filter form self-circulation through the self-circulation pump; the copper-nickel adding tank is connected with the liquid storage tank through a copper-nickel adding pump; the clean liquid tank is connected with the additive tank through an additive pump, and the clean liquid tank is connected with the crude foil engine through a liquid inlet pump; and the additive tank pumps an additive into the clean liquid tank through an additive pump, and the additive is uniformly mixed with the electrolyte and then enters the crude foil machine to electrolyze the copper-nickel alloy foil. Continuous, stable and efficient preparation of the ultrathin copper-nickel alloy foil can be achieved, the core problem that continuous production cannot be achieved in the prior art is solved, the production cost is reduced, and the product quality is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrolytic copper-nickel alloy foil, in particular to a continuous production device and method of ultra-thin electrolytic copper-nickel alloy foil. BACKGROUND

[0002] With the rapid development of new energy technology, lithium ion batteries have been widely used in electric vehicles, 3C electronics and energy storage fields due to their high energy density, long cycle life and other advantages. The negative current collector, as one of the core components of lithium ion batteries, directly affects the energy density, cycle stability and safety and reliability of the battery. At present, the mainstream negative current collector material on the market is pure copper foil, but pure copper foil has defects such as insufficient mechanical strength and easy oxidation corrosion, especially under high-rate charging and discharging or extreme working conditions, it is easy to break or deform, resulting in increased battery resistance and shortened cycle life.

[0003] Copper-nickel alloy foil is considered as an ideal material for the next generation of high-performance negative current collectors due to its high conductivity of copper and corrosion resistance and high strength characteristics of nickel. Its ultra-thin (usually thickness ≤10 μm) can further reduce battery mass and improve energy density, meeting the development trend of lightweight and high specific energy of lithium ion batteries. However, the existing preparation technology of copper-nickel alloy foil mostly adopts Hall tank multi-batch electrolysis or rolling process, which has the following key bottlenecks: Low production efficiency: Batch process requires frequent liquid change, cannot realize continuous operation, production capacity is limited, and cannot meet the customer's demand for large volume of copper-nickel alloy foil; Poor thickness uniformity: During the production process of Hall tank, the parameters such as electrolyte concentration and current density are easy to fluctuate, resulting in large thickness deviation of alloy foil and affecting the consistency of battery pole piece coating at customer end; High cost: The equipment utilization rate of Hall tank electrolysis process is low, manual intervention is more, and the scrap rate is high, which significantly increases the preparation cost of copper-nickel alloy foil and limits its popularization and application in the power field.

[0004] Therefore, it is of great significance to develop an electrolytic device and method that can realize the continuous production of ultra-thin copper-nickel alloy foil to improve the performance of lithium ion batteries, reduce the manufacturing cost and promote the industrial application of copper-nickel alloy foil.

[0005] The Chinese invention patent with the authorization announcement number CN111321437B discloses a copper-nickel alloy foil and an electrodeposition preparation method thereof. In the method, 5.0-10.0 L of additives are added per hour per cubic meter of electrolyte, the electrolyte is stirred uniformly, and then enters an electrolytic cell with a liquid supply flow rate of 45-60 m. The final copper foil is provided with a nickel-copper alloy layer and a pure copper layer. The prepared copper-nickel alloy foil includes a double-layer structure, the bottom layer has a nickel content of 3.6%, the upper layer has a nickel content of 8.8%, the thickness is 3-6 μm, and after testing, the upper layer nickel grains are uniformly doped in the copper grains, the roughness Rz of the rough surface is 1.64 um, the tensile strength is 539 Mpa, the elongation is 6.5%, the wettability is greater than or equal to 45×10 -3 N / m (characterized by a surface tension parameter), the thickness is uniform, and there is no tearing band phenomenon.

[0006] The Chinese invention patent with the publication number CN118581530A discloses a technical route to prepare a nickel-copper alloy foil with a thickness of 4-10 μm, a roughness of Rz≤3 μm, a nickel atomic fraction of 75.0-60.0 at%, a copper atomic fraction of 25.0-40.0 at%, a tensile strength of greater than or equal to 140 kgf / mm 2 , a maximum of about 180 kgf / mm 2 , an elongation of greater than or equal to 2%, and a durometer value of greater than or equal to 38.

[0007] Although the above two patents prepare copper-nickel alloy foils by different technical routes, they cannot realize the continuous production of copper-nickel alloy foils with high tensile strength. The scheme of CN118581530A can only be used for small-scale tests in a laboratory, and the sample preparation method is time-consuming and high-cost, and cannot realize continuous production. SUMMARY

[0008] The present application provides an ultra-thin electrolytic copper-nickel alloy foil continuous production device and method, which realizes the continuous, stable and efficient preparation of ultra-thin copper-nickel alloy foil, solves the core problem of the inability to continuously produce in the prior art, and reduces the production cost and improves the product quality.

[0009] One aspect of the present application provides an ultra-thin electrolytic copper-nickel alloy foil continuous production device, which comprises a liquid storage tank, an activated carbon filter, a sedimentation tank, a self-circulation pump, a copper-nickel addition tank, a copper-nickel addition pump, a liquid feeding pump, a diatomite filter, a clean liquid tank, an additive tank, an additive pump and a foil making machine. The liquid storage tank, the activated carbon filter, the sedimentation tank and the self-circulation pump are connected in sequence, and the liquid storage tank and the sedimentation tank and the activated carbon filter form a self-circulation through the self-circulation pump. The copper-nickel addition tank and the liquid storage tank are connected through the copper-nickel addition pump. One end of the diatomite filter is connected with the liquid storage tank through the liquid feeding pump, and the other end of the diatomite filter is connected with the clean liquid tank. The net liquid tank is connected with the additive tank through an additive pump, and the net liquid tank is connected with the foil making machine through an inlet liquid pump. The additive tank is connected with the net liquid tank through the additive pump, and the electrolyte is mixed with the additive and then enters the foil making machine to make the electrolytic copper-nickel alloy foil.

[0010] The above-mentioned continuous production device of the ultra-thin electrolytic copper-nickel alloy foil, wherein the total volume of the liquid storage tank is designed to be 15m 3 The volume of the liquid storage tank is greater than the running volume of the electrolyte for the electrolytic copper-nickel alloy foil of the device, and the electrolyte is stored in the liquid storage tank when the device is not running.

[0011] The above-mentioned continuous production device of the ultra-thin electrolytic copper-nickel alloy foil, wherein the copper-nickel additive pump and the additive pump are both metering pumps.

[0012] The above-mentioned continuous production device of the ultra-thin electrolytic copper-nickel alloy foil, wherein the sedimentation tank comprises a detachable filter bag, and when the copper ions and nickel ions are too high, the copper ion and nickel ion precipitation is adjusted by primary salt.

[0013] The above-mentioned continuous production device of the ultra-thin electrolytic copper-nickel alloy foil, wherein the width of the cathode roller of the foil making machine is 800mm, the diameter of the cathode roller is 850mm, and the winding roller is a gas expansion shaft plus an FRP tube core.

[0014] Another aspect of the present application provides a continuous production method of an ultra-thin electrolytic copper-nickel alloy foil, which adopts the above-mentioned continuous production device of the ultra-thin electrolytic copper-nickel alloy foil, and the method comprises the following steps: First, water is added to the copper-nickel additive tank and heated to a preset temperature, then copper sulfate pentahydrate and nickel sulfate hexahydrate are added, and stirring is performed to prepare electrolyte with a required concentration; After the electrolyte is completely dissolved, the electrolyte is pumped into the liquid storage tank, and the configuration process is repeated until the required electrolyte volume for system operation is reached; Then, the steam system is started to maintain the temperature in the liquid storage tank at a preset temperature, and the self-circulation pump is started to form a self-circulation between the liquid storage tank and the activated carbon filter; The electrolyte enters the diatomite filter through the liquid inlet pump, and the impurities are filtered through the diatomite filter, and the filtered electrolyte is delivered to the net liquid tank, while the additive is punched into the additive tank and the additive is punched into the net liquid tank through the additive pump; The electrolyte enters the net liquid tank and rises to the working liquid level, and the electrolyte is mixed with the additive; The inlet liquid pump is started, and after the electrolyte in the net liquid tank is uniformly mixed with the additive, the electrolyte is delivered to the foil making machine through the precision filter to make the copper-nickel alloy foil, and after the foil making, the electrolyte returns to the liquid storage tank through the overflow port of the electrolytic cell of the foil making machine (13), and the cycle is repeated.

[0015] The continuous production method of the ultra-thin electrolytic copper-nickel alloy foil, wherein the concentration of copper ions and nickel ions in the electrolyte is adjusted by a precipitation tank and a copper-nickel adding tank, the precipitation tank is provided with a filter bag and a chemical reagent adding port, when the concentration of copper ions and nickel ions is too high, chemical reagents are added to precipitate nickel salt and copper salt, and then the precipitate is filtered to adjust the concentration of copper ions and nickel ions in the electrolyte, and when the concentration of copper ions and nickel ions is too low or the device is normally operated, the copper-nickel adding tank is used for adding.

[0016] The continuous production method of the ultra-thin electrolytic copper-nickel alloy foil, wherein the additive is adjusted by an additive pump as a metering pump, and the flow adjustment range is 0-10.0 L / H.

[0017] The continuous production method of the ultra-thin electrolytic copper-nickel alloy foil, wherein when the copper-nickel alloy foil is produced by the foil forming machine, the current of the foil forming machine and the linear speed of the cathode roller are adjusted, and a gas expansion shaft is used for winding.

[0018] The continuous production method of the ultra-thin electrolytic copper-nickel alloy foil, wherein the preset temperature is 55-60 DEG C.

[0019] The continuous production device and method of the ultra-thin electrolytic copper-nickel alloy foil have the following beneficial effects: The present application can continuously produce 3.5-20.0 mu m copper-nickel alloy foil with a nickel content of 50-85 wt%, solve the problem that the copper-nickel alloy foil with high tensile strength cannot be continuously produced, realize the continuous, stable and efficient preparation of the ultra-thin copper-nickel alloy foil, solve the core problem that the existing technology cannot be continuously produced, and reduce the production cost and improve the product quality. The present application is a mechanized flow operation, the width of the produced copper-nickel alloy foil is larger than that of the sheet-shaped copper-nickel alloy foil produced in the laboratory, the length is longer, and the coiled copper-nickel alloy foil meets the needs of existing lithium ion battery manufacturers. The present application solves the problem of poor stability of copper-nickel ions and additives in the continuous production process, and makes the composition control more stable. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which: Figure 1 is a structural schematic diagram of the continuous production device of the ultra-thin electrolytic copper-nickel alloy foil; Figure 2 is a logic flow chart of the continuous production method of the ultra-thin electrolytic copper-nickel alloy foil; Figure 3 is a grain diagram of the copper-nickel alloy foil produced in Example 3; Figure 4 is an SEM diagram of the rough surface of the copper-nickel alloy foil produced in Example 3; Figure 5is a stress-strain curve of the copper-nickel alloy foil produced in Example 3; Figure 6 is a schematic diagram of the copper-nickel alloy foil winding face in the continuous production process of Example 3; Figure 7 is a laboratory sample preparation diagram of Comparative Example 1. DETAILED DESCRIPTION

[0021] In order to make the objects, features and advantages of the present application more apparent, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. The present application is illustrated in several embodiments in the drawings. However, the present application can be implemented 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.

[0022] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can be a mediating element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there can be a mediating element. The terms "vertical", "horizontal", "left", "right", "upper", "lower", and similar expressions used herein are for illustrative purposes only and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be construed as limiting the present application.

[0023] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0024] Referring to Figure 1 , one embodiment of the present application provides a continuous production device for ultra-thin electrolytic copper-nickel alloy foil, comprising a liquid storage tank 1, an activated carbon filter 2, a sedimentation tank 3, a self-circulation pump 4, a copper-nickel additive tank 5, a copper-nickel additive pump 6, a liquid feeding pump 7, a diatomite filter 8, a clean liquid tank 9, an additive tank 10, an additive pump 11, a liquid feeding pump 12, and a foil maker 13.

[0025] The liquid storage tank 1, the activated carbon filter 2, the sedimentation tank 3, and the self-circulation pump 4 are connected in sequence, and the liquid storage tank 1 and the sedimentation tank 3 and the activated carbon filter 2 form a self-circulation through the self-circulation pump 4.

[0026] The copper-nickel adding tank 5 and the liquid storage tank 1 are connected through a copper-nickel adding pump 6.

[0027] One end of the diatomite filter 8 is connected with the liquid storage tank 1 through a liquid feeding pump 7, and the other end of the diatomite filter 8 is connected with a clean liquid tank 9.

[0028] The clean liquid tank 9 is connected with an additive tank 10 through an additive pump 11, and the clean liquid tank 9 is connected with a foil making machine 13 through a liquid feeding pump 12.

[0029] The additive tank 10 adds additives into the clean liquid tank 9 through the additive pump 11, and the additives are mixed with the electrolyte and then enter the foil making machine 13 to electrolyze the copper-nickel alloy foil.

[0030] In the embodiment, the design total volume of the liquid storage tank 1 is 15m 3 The liquid storage volume is greater than the running volume of the electrolyte for electrolyzing the copper-nickel alloy foil in the device, and the electrolyte is completely stored in the liquid storage tank 1 when the device is not started.

[0031] The copper-nickel adding pump 6 and the additive pump 11 are both metering pumps.

[0032] The sedimentation tank 3 contains a detachable filter bag, and when the copper ions and nickel ions are too high, the main salt is adjusted by precipitating the copper ions and nickel ions.

[0033] The cathode roller of the foil making machine 13 has a width of 800mm and a diameter of 850mm, and the winding roller is a gas expansion shaft plus a FRP tube core.

[0034] Please refer to Figure 2 Another embodiment of the present application provides a continuous production method of the ultra-thin electrolytic copper-nickel alloy foil, which adopts the continuous production device of the ultra-thin electrolytic copper-nickel alloy foil, and the method comprises the following steps: The total volume of the electrolyte is 15m 3 Before starting the device for the first time, water is added into the copper-nickel adding tank 5 and heated to 55-60℃, then copper sulfate pentahydrate and nickel sulfate hexahydrate are added into the copper-nickel adding tank 5, and stirred to prepare the electrolyte with the required concentration; After the electrolyte is completely dissolved, the electrolyte is pumped into the liquid storage tank 1, and the configuration process is repeated until the electrolyte volume required by the system operation is reached; Then, the steam system is started to maintain the temperature in the liquid storage tank 1 at 55-60℃, and the self-circulation pump 4 is started to form a self-circulation between the liquid storage tank 1 and the activated carbon filter 2. The electrolyte enters the diatomite filter 8 through the liquid feeding pump 7, and the impurities are filtered through the diatomite filter 8. Preferably, the diatomite filter has a hanging earth amount of 1-2 kg, and the activated carbon is added in an amount of 100 g. The filtered electrolyte is delivered to the clean liquid tank 9, and the additive is injected into the clean liquid tank 9 through the additive pump 11 while the additive tank 10 is punched. The additive is regulated by the additive pump 11 as a metering pump, and the flow regulation range is 0-10.0 L / H. The additive supplement rate is confirmed by titration analysis of the electrolyte concentration per hour. The electrolyte enters the clean liquid tank 9 to the working liquid level, and the electrolyte is mixed with the additive. The liquid feeding pump 12 is started, and after the electrolyte in the clean liquid tank 9 is uniformly mixed with the additive, it is delivered to the foil making machine 13 through the precision filter to make the copper-nickel alloy foil. When the foil making machine 13 makes the copper-nickel alloy foil, the current of the foil making machine 13 and the linear speed of the cathode roller are adjusted, and the air expansion shaft is used for winding operation. After the foil making, the electrolyte returns to the storage tank 1 through the overflow port of the electrolytic cell of the foil making machine 13, and the cycle is repeated.

[0035] Specifically, the content of nickel ions and copper ions in the electrolyte is adjusted by the consumption of foil making and online monitoring results After the copper-nickel alloy foil making is completed, the copper-nickel alloy foil sample of full width is taken, the gram weight of each position is tested by the electronic balance, the roughness of the smooth surface and the rough surface is tested by the roughness meter, and the composition of the copper-nickel alloy foil at different meters is tested by ICP.

[0036] In addition, the concentration of copper ions and nickel ions in the electrolyte is adjusted by the precipitation tank 3 and the copper-nickel adding tank 5. The precipitation tank 3 is provided with a filter bag and a chemical reagent additive port. When the concentration of copper ions and nickel ions is too high, chemical reagents are added to precipitate nickel salt and copper salt, and then filtered to adjust the concentration of copper-nickel ions in the electrolyte. When the concentration is too low or the device is normally operated, the copper-nickel adding tank 5 is added.

[0037] The following will be described in detail in different embodiments: Example 1 After the storage tank is opened and the electrolyte is heated to 55℃ by steam, the liquid is fed. The copper-nickel adding tank injects salt solution into the storage tank at a rate of 5 L / H through the copper-nickel adding pump. Then, the clean liquid pump is started, and the electrolyte is filtered through the diatomite filter. When the liquid level of the clean liquid tank reaches 900 mm, the additive in the additive tank is injected into the clean liquid tank at a rate of 10 L / H. Then, the liquid feeding pump is started, and the liquid feeding rate is 18 m 3 / H. At the same time, the foil making current is adjusted to 5000 A, and the linear speed of the cathode roller is set to 1.962 m / min. During the continuous winding of the winding roller, the copper-nickel alloy foil with a thickness of 10 μm is finally obtained.

[0038] The detected 10 μm roll-shaped copper-nickel alloy foil weight difference is 1.1 g / mm 2 , the Ra of the smooth surface is 0.33 μm, the Ra of the rough surface is 0.45 μm, the nickel content is 63 wt%, the copper content is 36 wt%, and the copper-nickel composition difference is less than 1%.

[0039] Example 2 After the electrolyte in the liquid storage tank is heated to 55°C by steam, the liquid is added, and the copper-nickel additive tank injects high-concentration copper ion and nickel ion solution into the liquid storage tank at a rate of 4 L / H through the copper-nickel additive pump. Subsequently, the clean liquid pump is started, and the electrolyte is filtered through the diatomite filter. When the liquid level of the clean liquid tank reaches 900 mm, the additive in the additive tank should be injected into the clean liquid tank at a rate of 5 L / H. Then, the liquid inlet pump is started, and the liquid inlet rate is 16 m 3 / H. At the same time, the foil current is adjusted to 5000 A, and the linear speed of the cathode roller is set to 2.061 m / min. During the continuous winding of the winding roller, the copper-nickel alloy foil with a thickness of 10 μm is finally obtained.

[0040] The detected 8 μm roll-shaped copper-nickel alloy foil weight difference is 0.81 g / mm 2 , the Ra of the smooth surface is 0.29 μm, the Ra of the rough surface is 0.36 μm, the nickel content is 59.2 wt%, the copper content is 40.5 wt%, and the copper-nickel composition difference is less than 1%.

[0041] Example 3 After the electrolyte in the liquid storage tank is heated to 55°C by steam, the liquid is added, and the copper-nickel additive tank injects high-concentration copper ion and nickel ion solution into the liquid storage tank at a rate of 4 L / H through the copper-nickel additive pump. Subsequently, the clean liquid pump is started, and the electrolyte is filtered through the diatomite filter. When the liquid level of the clean liquid tank reaches 900 mm, the additive in the additive tank should be injected into the clean liquid tank at a rate of 5 L / H. Then, the liquid inlet pump is started, and the liquid inlet rate is 16 m 3 / H. At the same time, the foil current is adjusted to 5000 A, and the linear speed of the cathode roller is set to 2.061 m / min. During the continuous winding of the winding roller, the copper-nickel alloy foil with a thickness of 10 μm is finally obtained.

[0042] The detected 8 μm roll-shaped copper-nickel alloy foil weight difference is 0.81 g / mm 2 , the Ra of the smooth surface is 0.29 μm, the Ra of the rough surface is 0.36 μm, the nickel content is 59.2 wt%, the copper content is 40.5 wt%, and the copper-nickel composition difference is less than 1%.

[0043] Example 4 The electrolyte was heated to 55°C by steam and then the liquid was fed into the tank. The high concentration copper and nickel ion solution was fed into the tank at a rate of 3.0 L / H. Then the liquid pump was started and the electrolyte was filtered through the diatomite filter. When the liquid level of the tank reached 900 mm, the additive in the additive tank was fed into the tank at a rate of 8.0 L / H. Then the liquid pump was started and the liquid feeding rate was 10 m 3 / H. At the same time, the current was adjusted to 5000 A and the linear speed of the cathode roller was set to 3.043 m / min. During the continuous winding of the winding roller, the copper-nickel alloy foil with a thickness of 10 μm was obtained.

[0044] The weight difference of the 5 μm copper-nickel alloy foil was 0.64 g / mm 2 , the Ra of the smooth surface was 0.24 μm, the Ra of the rough surface was 0.27 μm, the nickel content was 67.3%, the copper content was 32.5%, and the element composition difference of copper and nickel was less than 1%.

[0045] Comparative Example 1 A cathode plate with a size of 150 mm x 100 mm was used for the electroplating operation in a Hull cell. A current of 10 A was applied for 5 min. After the electroplating was completed, a copper-nickel alloy foil with a size of 150 mm x 100 mm x 6 μm was peeled off from the cathode plate. By repeating the above electroplating and peeling process, 5 copper-nickel alloy foil samples were prepared. The weight test of the samples showed that the weight difference of the copper-nickel alloy foil was 2.64 g / mm 2 , the element composition difference of copper and nickel was 6 wt%, the average roughness of the rough surface was 0.33 μm, and the average roughness of the smooth surface was 0.46 μm.

[0046] Comparative Example 2 In a Hull cell, a cathode plate with a size of 270 mm long x 240 mm wide was used for the electroplating operation. A current of 33 A was applied for 5 min. After the electroplating was completed, a copper-nickel alloy foil with a size of 270 mm long x 240 mm wide x 6 μm thick was peeled off from the cathode plate. By repeating the above electroplating and peeling process, 5 copper-nickel alloy foil samples were prepared. The weight test of the samples showed that the weight difference of the copper-nickel alloy foil was 2.86 g / mm 2 , the element composition difference of copper and nickel was 4 wt%. At the same time, the roughness of the samples was measured, the average roughness of the rough surface was 0.28 μm, and the average roughness of the smooth surface was 0.37 μm.

[0047] Table 1 summarizes the test results of the various examples and comparative examples: Table 1

[0048] As can be seen from Table 1, the performance of the copper-nickel alloy foil obtained by each embodiment of the present application is obviously superior to each of the comparative examples, especially the weight and copper-nickel composition of the copper-nickel alloy foil.

[0049] In addition, please refer to Figures 3 to 7 , Figure 3 is a grain diagram of the copper-nickel alloy foil produced in Example 3, from Figure 3 It can be seen that the grain distribution of the obtained foil surface is relatively uniform, and there is no obvious hole and coarse grain phenomenon. This further indicates that the ultra-thin electrolytic copper-nickel alloy foil produced by the present application has good microstructure and quality stability. Uniform grain distribution helps to improve the performance of the copper-nickel foil, such as strength, elongation, etc.

[0050] Figure 4 is a SEM diagram of the rough surface of the copper-nickel alloy foil produced in Example 3, from Figure 4 It can be seen that the foil surface is relatively smooth, showing a good electroplated layer state.

[0051] Figure 5 The stress-strain curve, tensile strength and elongation data of the copper-nickel alloy foil produced in Example 3 are shown, from Figure 5 It can be seen that the tensile strength of the continuously produced copper-nickel alloy foil is between 145-170 MPa, and the elongation is between 2.5-3.5%.

[0052] Figure 6 is a schematic diagram of the winding foil surface of the copper-nickel alloy foil in the continuous production process of Example 3. The present application can continuously wind the copper-nickel alloy foil, and the winding width is the width of the cathode roller, and the length can be wound up to 5000m at the longest.

[0053] Figure 7 is a laboratory sample preparation diagram of Comparative Example 1, from Figure 7 It can be seen that the alloy foil prepared by the titanium plate has a smaller size and cannot be continuously produced, and needs to be frequently replaced with electrolyte to maintain the normal appearance of the foil surface.

[0054] In summary, the ultra-thin electrolytic copper-nickel alloy foil continuous production device and method proposed by the present application has the following beneficial effects: The application can continuously produce 3.5-20.0 mu m copper-nickel alloy foil with a nickel content in the range of 50-85 wt%, solve the problem that high tensile strength copper-nickel alloy foil cannot be continuously produced, realize the continuous, stable and efficient preparation of ultra-thin copper-nickel alloy foil, solve the core problem that existing technologies cannot be continuously produced, and reduce the production cost and improve the product quality. The application is mechanized and waterline operation, the width of the copper-nickel alloy foil produced is larger than that of the sheet-shaped copper-nickel alloy foil produced in the laboratory, the meter number is longer, and the coiled copper-nickel alloy foil meets the needs of existing lithium ion battery manufacturers. The application solves the problem of poor stability of copper-nickel ions and additives in the continuous production process, and makes the composition control more stable.

[0055] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0056] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application. It should be noted that, for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A continuous production apparatus for ultra-thin electrolytic copper-nickel alloy foil, characterized in that, Includes a storage tank (1), an activated carbon filter (2), a sedimentation tank (3), a self-circulating pump (4), a copper-nickel addition tank (5), a copper-nickel addition pump (6), a liquid loading pump (7), a diatomaceous earth filter (8), a clean liquid tank (9), an additive tank (10), an additive pump (11), a liquid inlet pump (12), and a foil making machine (13); The storage tank (1), activated carbon filter (2), sedimentation tank (3), and self-circulating pump (4) are connected in sequence. The storage tank (1), sedimentation tank (3), and activated carbon filter (2) form a self-circulation through the self-circulating pump (4). The copper-nickel addition tank (5) and the storage tank (1) are connected by a copper-nickel addition pump (6); One end of the diatomaceous earth filter (8) is connected to the storage tank (1) via the upper liquid pump (7), and the other end of the diatomaceous earth filter (8) is connected to the clean liquid tank (9); The purified liquid tank (9) is connected to the additive tank (10) via the additive pump (11), and the purified liquid tank (9) is connected to the foil production machine (13) via the inlet pump (12). The additive tank (10) pumps the additive into the clean liquid tank (9) through the additive pump (11), and after mixing with the electrolyte, it enters the foil production machine (13) to electrolyze the copper-nickel alloy foil.

2. The continuous production apparatus for ultra-thin electrolytic copper-nickel alloy foil according to claim 1, characterized in that, The total designed volume of the liquid storage tank (1) is 15m³. 3 The storage volume is larger than the operating volume of the electrolyte for electrolyzing copper-nickel alloy foil in the device. When the device is not running, all the electrolyte is stored in the storage tank (1).

3. The continuous production apparatus for ultra-thin electrolytic copper-nickel alloy foil according to claim 1, characterized in that, Both the copper-nickel addition pump (6) and the additive pump (11) are metering pumps.

4. The continuous production apparatus for ultra-thin electrolytic copper-nickel alloy foil according to claim 1, characterized in that, The sedimentation tank (3) includes a removable filter bag. When the levels of copper and nickel ions are too high, the main salt is used to precipitate the copper and nickel ions.

5. The continuous production apparatus for ultra-thin electrolytic copper-nickel alloy foil according to claim 1, characterized in that, The cathode roller of the foil making machine (13) has a width of 800mm and a diameter of 850mm. The winding roller is an air-expanded shaft with an FRP core.

6. A continuous production method for ultrathin electrolytic copper-nickel alloy foil, characterized in that, The method using the continuous production apparatus for ultra-thin electrolytic copper-nickel alloy foil according to any one of claims 1 to 5 includes: First, add water to the copper-nickel addition tank (5) and heat it to the preset temperature. Then, add copper sulfate pentahydrate and nickel sulfate hexahydrate to it and stir to prepare an electrolyte of the required concentration. After the electrolyte has completely dissolved, pump the electrolyte into the storage tank (1) and repeat this preparation process until the electrolyte volume required for system operation is reached. Next, the steam system is started to maintain the temperature inside the storage tank (1) at the preset temperature, and the self-circulating pump (4) is turned on to form a self-circulation between the storage tank (1) and the activated carbon filter (2); The electrolyte enters the diatomaceous earth filter (8) through the top liquid pump (7), filters impurities through the diatomaceous earth filter (8), and the filtered electrolyte is transported to the clean liquid tank (9). At the same time, additives are injected into the additive tank (10) and injected into the clean liquid tank (9) through the additive pump (11). The electrolyte enters the clean liquid tank (9) and is raised to the working liquid level. The electrolyte and additives are then mixed. Start the inlet pump (12), and after the electrolyte and additives in the clean liquid tank (9) are mixed evenly, they are transported to the foil making machine (13) through a precision filter to make copper-nickel alloy foil. After foil making, the electrolyte returns to the storage tank (1) through the overflow port of the electrolytic cell of the foil making machine (13) and is circulated in sequence.

7. The continuous production method for ultrathin electrolytic copper-nickel alloy foil according to claim 6, characterized in that, The concentrations of copper and nickel ions in the electrolyte are adjusted by a sedimentation tank (3) and a copper-nickel addition tank (5). The sedimentation tank (3) is equipped with a filter bag and a chemical reagent additive port. When the concentrations of copper and nickel ions are too high, chemical reagents are added to precipitate the nickel and copper salts and then filter them to adjust the concentration of copper and nickel ions in the electrolyte. When the concentrations are too low or when the device is operating normally, copper-nickel addition tank (5) is used to add them.

8. The continuous production method for ultrathin electrolytic copper-nickel alloy foil according to claim 6, characterized in that, The additive is controlled by using an additive pump (11) as a metering pump, with a flow rate adjustment range of 0-10.0 L / H.

9. The continuous production method for ultrathin electrolytic copper-nickel alloy foil according to claim 6, characterized in that, When the foil making machine (13) is making copper-nickel alloy foil, the current and cathode roller speed of the foil making machine (13) are adjusted, and the air shaft is used for winding.

10. The continuous production method for ultrathin electrolytic copper-nickel alloy foil according to claim 6, characterized in that, The preset temperature is 55-60℃.

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