Composite metal strip continuous production equipment

Abstract

The present invention discloses a composite metal strip continuous production equipment, comprising: an unwinding mechanism: used for continuously unwinding a substrate; an extrusion molding device: used for extruding and molding a metal layer on at least one side of the substrate to obtain a composite metal strip; a winding mechanism: used for winding the prepared composite metal strip; the extrusion molding device comprises an extrusion roller group, the extrusion roller group comprises two extrusion rollers whose axes are parallel to each other; a feeding device for adding molten metal material is provided on the feed side of the two extrusion rollers; a high temperature zone for keeping the molten metal material in a molten state is provided on the feed side of the extrusion roller group, and a cooling zone for cooling and shaping the composite metal strip is provided on the discharge side of the extrusion roller group; a guide mechanism for allowing the substrate to pass between the two extrusion rollers is provided between the unwinding mechanism and the winding mechanism. Not only can the large-scale continuous production requirements of the composite metal strip be met, but the thickness of the metal layer can be thinner, and the quality of the composite metal strip is more stable.

Description

Technical Field

[0001] The invention relates to a composite metal strip production device, in particular to a composite metal strip continuous production device. Background Art

[0002] Metals have high capacity (theoretical 3860 mAh / g), low density (0.59 g / cm3), and low electrochemical potential (-3.04 V vs. standard hydrogen electrode). Therefore, metal secondary batteries with metal as negative electrodes have excellent performance in terms of high voltage and high energy density compared to lithium-ion batteries with graphite negative electrodes.

[0003] Existing composite metal strips generally adopt a processing method of roll forming of metal strips and substrates. Metal strips generally adopt an extrusion molding process, such as a metal strip production device disclosed in Chinese patent publication number CN204564801U, and a metal strip processing method disclosed in Chinese patent publication number CN101497088B, both of which adopt extrusion molding to produce metal strips. The composite metal strips produced by the existing extrusion molding process have the disadvantage of being thicker. When thicker metal strips are used in metal batteries, the negative electrode capacity far exceeds the positive electrode capacity, which results in a waste of negative electrode metal, while also increasing the volume and weight of the battery, reducing the volume and mass energy density of the battery, and is not conducive to the improvement of the ultimate energy density of the metal battery.

[0004] The Chinese patent with publication number CN206992217U discloses a composite metal strip production device, which is provided with a frame, on which upper and lower rollers are mounted, a current collector unwinding device, a lithium strip unwinding device and a protective film unwinding device are provided upstream of the rollers, an unwinding guide roller is provided downstream of the protective film unwinding device, a composite metal strip winding device and a protective film winding device corresponding to the protective film unwinding device are provided downstream of the rollers, and a winding guide roller is provided upstream of the protective film winding device. The composite metal strip production device uses roll forming to combine the current collector and the metal strip. Since the metal strip itself is relatively thick and the metal strip and the current collector are combined together only by simple rolling, there is a problem of insufficient bonding strength.

[0005] Of course, there are also some technical solutions in the prior art that use non-rolling forming methods to process composite metal strips. For example, the Chinese patent with publication number CN109360934A discloses a method for preparing an ultra-thin composite metal strip. In a high-purity argon atmosphere, after heating the lithium ingot to a molten state, the roughened conductive substrate is immersed in liquid lithium to slurry and slowly pulled out. The thickness of the slurry is adjusted by the rollers, and the strip is rolled up after air cooling to obtain an ultra-thin composite metal strip with lithium on both sides with a total thickness of 10 to 50 μm. The method for preparing the ultra-thin composite metal strip uses the method of immersing the substrate in molten metal to slurry the strip to produce the composite metal strip. However, due to the high viscosity of the molten metal, there is a large difference in the thickness of the slurry on the substrate, and there may be no slurry in some areas of the substrate. Due to the effect of gravity, there is also a large difference in the slurry on the upper and lower sides of the substrate. It is difficult to stably slurry the lower side of the substrate, resulting in the quality of the composite metal strip prepared by the method for preparing the ultra-thin composite metal strip being unstable. Summary of the invention

[0006] In view of this, the object of the present invention is to provide a composite metal strip continuous production device, which can not only meet the large-scale continuous production requirements of the composite metal strip, but also the thickness of the metal layer can be thinner and the quality of the composite metal strip is more stable.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A composite metal strip continuous production device, comprising:

[0009] Unwinding mechanism: used for continuously unwinding substrate;

[0010] Extrusion molding device: used for extruding a metal layer on at least one side of the substrate to obtain a composite metal strip;

[0011] Winding mechanism: used for winding the prepared composite metal strip;

[0012] The extrusion molding device comprises an extrusion roller group, wherein the extrusion roller group comprises two extrusion rollers whose axes are parallel to each other; a feeding device for adding molten metal material is provided on the feeding side of the two extrusion rollers;

[0013] The feed side of the extrusion roller group is provided with a high temperature zone for keeping the molten metal material in a molten state, and the discharge side of the extrusion roller group is provided with a cooling zone for cooling and shaping the composite metal strip;

[0014] A guiding mechanism for allowing the substrate to pass through between the two squeezing rollers is provided between the unwinding mechanism and the winding mechanism.

[0015] Furthermore, a roll gap adjusting mechanism for adjusting the roll gap is provided between the two squeezing rolls.

[0016] Furthermore, when the substrate is always in contact with one of the extrusion rollers, the feeding device includes a feeding mechanism for feeding molten metal material to the side of the substrate facing the other extrusion roller;

[0017] When an extrusion gap is respectively provided between the substrate and the two extrusion rollers, the feeding device comprises two feeding mechanisms respectively used for feeding molten metal material to two sides of the substrate.

[0018] Furthermore, when the axes of the two squeezing rollers are located on the same horizontal plane, the upper side of the two squeezing rollers is the feeding side.

[0019] Furthermore, when an extrusion gap is respectively provided between the substrate and the two extrusion rollers, the guide mechanism guides the substrate to pass through between the two extrusion rollers in a vertical downward direction.

[0020] Furthermore, the guide mechanism guides the substrate and makes the extrusion gap between the substrate and the two extrusion rollers equal, or makes the difference between the extrusion gap between the substrate and the two extrusion rollers within a set range.

[0021] Furthermore, the feeding mechanism includes a feeding pump for conveying molten metal material into the high temperature zone, or the feeding mechanism includes a powder spraying device for conveying metal particles or metal powder into the high temperature zone, and the feeding device also includes a melting heating mechanism arranged in the high temperature zone and used to melt the metal particles or metal powder to form molten metal material.

[0022] Furthermore, a drainage device for diverting the molten metal material to the feed side of the two extrusion rollers is provided in the high temperature zone.

[0023] Furthermore, the drainage device includes a drainage plate arranged in the high temperature zone.

[0024] Furthermore, the guide plates are provided in two pieces, and the two guide plates are respectively located below the feeding device.

[0025] Furthermore, a heating zone for heating is provided on the opposite sides of the two guide plates, and a constant temperature zone is formed between the two guide plates.

[0026] Furthermore, a cold air device is provided in the cooling zone; the cold air device includes a cold air unit arranged corresponding to the side of the substrate on which the metal layer is provided, and the cold air unit includes an air guide plate; the outer side of the air guide baffle facing away from the substrate is provided with a cold air channel for blowing cooling medium on the discharge side of the extrusion roller group, and a reflux channel for reflux of cooling medium is formed between the air guide baffle and the substrate; or, a cold air channel for blowing cooling medium on the discharge side of the extrusion roller group is formed between the air guide baffle and the substrate, and the outer side of the air guide baffle facing away from the substrate is provided with a reflux channel for reflux of cooling medium.

[0027] Furthermore, the number of the cold air units is two and they are respectively located on two sides of the substrate.

[0028] Furthermore, the two air guide plates are symmetrically arranged relative to the symmetric planes of the two squeezing rollers.

[0029] Furthermore, it also includes a scraper for scraping off the molten metal material attached to the extrusion roller.

[0030] Furthermore, a collecting box is provided below the scraper.

[0031] Furthermore, the substrate may be, but not limited to, copper strip, aluminum strip, steel strip, nickel strip, silver strip, gold strip, or a strip composite of metal material and non-metal material; or the substrate may be, but not limited to, release paper.

[0032] Furthermore, the substrate is a mesh foil or the strip is provided with through holes in an array.

[0033] Furthermore, the molten metal material includes but is not limited to lithium metal, sodium metal, potassium metal, magnesium metal, calcium metal, zinc metal, aluminum metal or silver metal; or the metal material includes but is not limited to an alloy formed by a proportion of at least two of lithium metal, sodium metal, potassium metal, magnesium metal, calcium metal, zinc metal, aluminum metal and silver metal.

[0034] Furthermore, a finishing area is provided between the extrusion molding device and the winding mechanism.

[0035] Furthermore, the finishing area is provided with a laser finishing device for finishing the composite metal strip.

[0036] Furthermore, at least one group of finishing rollers is arranged at intervals in the finishing area, and each group of finishing rollers includes two correspondingly arranged finishing rollers.

[0037] Furthermore, between two adjacent finishing roller groups, the gap between the rollers of the finishing roller group on the side close to the extrusion forming device is larger than the gap between the rollers of the finishing roller group on the side close to the winding mechanism.

[0038] Furthermore, a heat preservation device for maintaining the rolling temperature within a set range is provided in the finishing area.

[0039] Furthermore, it also includes a trimming device, which is arranged in the finishing area or between the finishing area and the winding mechanism.

[0040] Furthermore, a film laminating mechanism for laminating an isolation film onto at least one side surface of the composite metal strip is provided at the front end of the winding mechanism.

[0041] Furthermore, the film composite mechanism comprises a film unwinding mechanism for unwinding the isolation film and a composite roller group for composite the composite metal strip and the isolation film together.

[0042] The beneficial effects of the present invention are:

[0043] The continuous production equipment for composite metal strips of the present invention utilizes a guiding mechanism to allow the substrate to pass through two extrusion rollers, and then utilizes an extrusion roller group to roll the molten metal material onto the side of the substrate. After rolling, it is quickly cooled and shaped, which can meet the production requirements of the composite metal strips. Compared with the prior art method of directly rolling the metal strip and the substrate for composite bonding, the composite metal strip obtained by the continuous production equipment for composite metal strips of the present invention has better bonding strength, and the metal layer can be thinner, even reaching less than 10um; compared with the existing method of producing composite metal strips by immersing the substrate in molten metal and hanging a paddle, the composite metal strip produced by the continuous production equipment for composite metal strips of the present invention has a uniform thickness of the metal layer, does not have the defect of no metal covering in certain areas of the substrate, and has a more stable quality; in summary, the continuous production equipment for composite metal strips of the present invention can not only meet the requirements of large-scale continuous production of composite metal strips, but also the thickness of the metal layer can be thinner, and the quality of the composite metal strips is also more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration:

[0045] Figure 1 This is a schematic structural diagram of Embodiment 1 of the composite metal strip continuous production equipment of the present invention;

[0046] Figure 2 for Figure 1 Detailed drawing A;

[0047] Figure 3 It is a structural schematic diagram of the second air inlet and outlet mode of the cooling air device;

[0048] Figure 4 This is a schematic structural diagram of embodiment 2 of the composite metal strip continuous production equipment of the present invention.

[0049] Description of reference numerals:

[0050] 1-substrate; 2-composite metal strip; 3-extrusion roller; 4-feeding pump; 4a-nozzle; 5-guiding plate; 6-heating zone; 7-constant temperature zone; 8-air guide plate; 8a-cold air channel; 8b-return channel; 9-air inlet gap; 10-scraper; 11-collection box; 12-finishing roller; 13-insulating device; 14-unwinding tension adjusting roller; 15-winding tension adjusting roller; 16-unwinding roller; 17-winding roller; 18-pressure adjusting mechanism; 19-guide roller; 20-isolating film; 21-diaphragm unwinding mechanism; 22-composite roller group. DETAILED DESCRIPTION

[0051] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0052] Example 1

[0053] like Figure 1 The figure is a schematic diagram of the structure of an embodiment of the composite metal strip continuous production equipment of the present invention. The composite metal strip continuous production equipment of this embodiment includes:

[0054] Unwinding mechanism: comprising an unwinding roller 16, used for continuously unwinding the substrate 1;

[0055] Extrusion molding device: used for extruding a metal layer on at least one side of the substrate 1 to obtain a composite metal strip 2;

[0056] The winding mechanism includes a winding roller 17 for winding the prepared composite metal strip 2;

[0057] The extrusion molding device includes an extrusion roller group, which includes two extrusion rollers 3 whose axes are parallel to each other; a feeding device for adding molten metal material is provided on the feeding side of the two extrusion rollers 3;

[0058] The feeding side of the extrusion roller group is provided with a high temperature zone for keeping the molten metal material in a molten state, and the discharging side of the extrusion roller group is provided with a cooling zone for cooling and shaping the composite metal strip 2;

[0059] A guide mechanism for allowing the substrate 1 to pass between the two squeezing rollers 3 is provided between the unwinding mechanism and the rewinding mechanism. The guide mechanism includes a plurality of guide rollers 19 .

[0060] Furthermore, a roll gap adjusting mechanism for adjusting the roll gap is provided between the two extrusion rollers 3, which can adjust the roll gap width between the two extrusion rollers 3, thereby controlling the forming thickness of the metal layer.

[0061] Further, when the substrate 1 and one of the extrusion rollers 3 are always in contact, the feeding device includes a feeding mechanism for adding molten metal material to the side of the substrate 1 facing the other extrusion roller; when an extrusion gap is provided between the substrate 1 and the two extrusion rollers 3, the feeding device includes two feeding mechanisms for adding molten metal material to both sides of the substrate. In this embodiment, an extrusion gap is provided between the substrate 1 and the two extrusion rollers 3.

[0062] Further, when the axes of the two extrusion rollers 3 are located on the same horizontal plane, the upper side of the two extrusion rollers 3 is the feeding side. The guide mechanism of this embodiment guides the substrate 1 to pass between the two extrusion rollers 3 in a vertical downward direction. Specifically, the guide mechanism guides the substrate 1 and makes the extrusion gap between the substrate 1 and the two extrusion rollers 3 equal, or makes the difference between the extrusion gap between the substrate 1 and the two extrusion rollers 3 within a set range. In this embodiment, the extrusion gap between the substrate 1 and the two extrusion rollers 3 is equal, that is, the thickness of the metal layer extruded on both sides of the substrate 1 is equal.

[0063] Furthermore, the feeding mechanism includes a feeding pump 4 for conveying molten metal material into the high temperature zone, or the feeding mechanism includes a powder spraying device for conveying metal particles or metal powder into the high temperature zone, and the feeding device also includes a melting heating mechanism arranged in the high temperature zone and used to melt the metal particles or metal powder and form molten metal material. The two feeding mechanisms of this embodiment are respectively located on both sides of the vertical symmetry plane between the two extrusion rollers 3, so as to achieve the technical purpose of conveying metal to both sides of the substrate at the same time. The feeding mechanism of this embodiment includes a feeding pump 4 for conveying molten metal into the high temperature zone, and the feeding pump 4 is provided with a nozzle 4a for conveying molten metal into the high temperature zone.

[0064] Furthermore, a drainage device for diverting the molten metal material to the top of the two extrusion rollers 3 is provided in the high temperature zone. The drainage device of this embodiment includes a drainage plate 5 arranged in the high temperature zone. Specifically, the drainage plate 5 of this embodiment is provided in two pieces, and the two drainage plates 5 are respectively located below the two feeding devices, and the two drainage plates 5 of this embodiment are symmetrically arranged relative to the vertical symmetry plane between the two extrusion rollers 3, so that the molten metal material located on both sides of the substrate 1 can be respectively diverted to between the two extrusion rollers 3. The two drainage plates 4 of this embodiment are provided with a heating zone 6 for heating on the opposite side, and a constant temperature zone 7 is formed between the two drainage plates 5. A heating device is provided in the heating zone 6, and the temperature in the constant temperature zone 7 is used to keep the molten metal material in a molten state, or to melt the metal particles or metal powder and keep it in a molten state.

[0065] Furthermore, a cooling device is provided in the cooling zone. The cooling device includes a cooling unit corresponding to the side of the substrate 1 provided with the metal layer. In this embodiment, two cooling units are provided, and the two cooling units are respectively located on both sides of the substrate 1. The cooling unit includes an air guide plate 8; the outer side of the air guide baffle plate facing away from the substrate 1 is provided with a cooling channel 8a for blowing cooling medium on the discharge side of the extrusion roller group, and a reflux channel 8b for reflux of cooling medium is formed between the air guide baffle plate and the substrate 1, such as Figure 1 and 2 As shown; or, a cold air channel for blowing the cooling medium on the discharge side of the extrusion roller group is formed between the air guide baffle and the substrate 1, and a reflux channel for reflux of the cooling medium is provided on the outer side of the air guide baffle facing away from the substrate 1, such as Figure 3 Specifically, an air inlet gap 9 is provided between the air guide plate 8 and the squeezing roller 3, and the air inlet gap is connected to the cold air channel and the return air channel.

[0066] Furthermore, the composite metal strip continuous production equipment of this embodiment also includes a scraper 10 for scraping off metal attached to the extrusion roller 3. A collecting box 11 is provided below the scraper 10 of this embodiment to collect the scraped metal for recycling.

[0067] The substrate 1 of this embodiment is made of but not limited to copper strip, aluminum strip, steel strip, nickel strip, silver strip, gold strip or a strip composite of metal material and non-metal material. The substrate 1 is made of mesh foil or strip with through holes arranged in an array, and the metal layers composited on both sides of the substrate 1 are connected as a whole through the mesh or through holes arranged on the substrate 1, which can effectively improve the bonding strength between the metal layer and the substrate. The molten metal material of this embodiment is made of but not limited to metal lithium, metal sodium, metal potassium, metal magnesium, metal calcium, metal zinc, metal aluminum or metal silver; or the metal material is made of but not limited to an alloy formed by at least two of metal lithium, metal sodium, metal potassium, metal magnesium, metal calcium, metal zinc, metal aluminum and metal silver.

[0068] Furthermore, a finishing zone is provided between the extrusion forming device and the winding mechanism of the present embodiment. At least one group of finishing roller groups is provided at intervals in the finishing zone, and each group of finishing roller groups includes two correspondingly provided finishing rollers 12. Four groups of finishing roller groups are provided in the finishing zone of the present embodiment. Of course, according to actual needs, the finishing roller groups can also be provided as 1 group, 2 groups, 3 groups, 5 groups or more than 5 groups. The principles are equivalent and will not be described one by one. Of course, other methods can also be used to achieve finishing of the composite metal strip 2, such as providing a laser finishing device for finishing the composite metal strip in the finishing zone, etc., which will not be described again.

[0069] Specifically, between two adjacent finishing roller groups, the gap between the finishing roller groups on the side close to the extrusion forming device is greater than or equal to the gap between the finishing roller groups on the side close to the winding mechanism. Specifically, the finishing roller group also includes a pressure regulating mechanism 18 for regulating the rolling pressure. Between two adjacent finishing roller groups, the rolling pressure of the finishing roller group on the side close to the extrusion forming device is less than or equal to the rolling pressure of the finishing roller group on the side close to the winding mechanism, gradually controlling the thickness of the metal layer on the composite metal strip and making the surface accuracy of the composite metal strip reach the set value.

[0070] Furthermore, in the finishing zone of this embodiment, a heat preservation device 13 is provided to maintain the rolling temperature within a set range. Within the set temperature range, the metal can be softened to facilitate further rolling.

[0071] Furthermore, among the two finishing rollers 12 in the last group of finishing rollers, at least one of the finishing rollers 12 is provided with a rolling needle for rolling holes on the corresponding metal layer of the composite metal strip 2. In this embodiment, the two finishing rollers 12 in the last group of finishing rollers are provided with rolling needles, so that holes can be processed on the upper and lower metal layers of the composite metal strip 2 at the same time. Of course, it is also possible to adopt a method of setting a rolling hole area at the rear side of the finishing area. In this case, a rolling hole area is provided with a rolling roller group or a pressing plate group for processing holes on at least one metal layer of the composite metal strip 2. The rolling roller group or the pressing plate group is provided with a rolling needle for rolling the holes, which can also meet the technical purpose of processing holes on the metal layer of the composite metal strip 2. The principles are equivalent and will not be repeated.

[0072] Specifically, the rolling needle of this embodiment is a nanometer-scale rolling needle, and the outer diameter of the rolling needle is greater than or equal to 1nm and less than or equal to 1um. The spacing between two adjacent rolling needles satisfies:

[0073] L≤kδ

[0074] Wherein, L is the pore spacing of the nanoscale pores; k is a coefficient, and k ≥ 1; δ is the thickness of the diffusion control layer.

[0075] The thickness of the diffusion control layer is:

[0076]

[0077] Wherein, δ is the thickness of the diffusion control layer; D is the diffusion coefficient; and t is the time.

[0078] Furthermore, a film laminating mechanism for laminating the isolation film 20 on at least one side of the composite metal strip 2 is provided between the finishing zone and the winding mechanism of the present embodiment. The film laminating mechanism of the present embodiment laminates the isolation film 20 on the lower side of the composite metal strip 2. Specifically, the film laminating mechanism of the present embodiment includes a film unwinding mechanism 21 for unwinding the isolation film 20 and a laminating roller group 22 for laminating the composite metal strip 2 with the isolation film 20. By laminating a separable isolation film on at least one side of the composite metal strip 2, when the metal layer is made of soft metal, adhesion between the metal layers of the rolled composite metal strip 2 can be avoided.

[0079] The continuous production equipment for composite metal strips in this embodiment utilizes a guiding mechanism to allow the substrate to pass through two extrusion rollers, and then utilizes an extrusion roller group to roll the molten metal material onto the side of the substrate. After rolling, it is quickly cooled and shaped, which can meet the production requirements of the composite metal strips. Compared with the prior art method of directly rolling the metal strip and the substrate for composite bonding, the composite metal strip obtained by the continuous production equipment for composite metal strips of the present invention has better bonding strength, and the metal layer can be thinner, even reaching less than 10um; compared with the existing method of producing composite metal strips by immersing the substrate in molten metal and hanging a paddle, the composite metal strip produced by the continuous production equipment for composite metal strips of the present invention has a uniform thickness of the metal layer, does not have the defect of no metal covering in certain areas of the substrate, and has a more stable quality; in summary, the continuous production equipment for composite metal strips of the present invention can not only meet the requirements of large-scale continuous production of composite metal strips, but also the thickness of the metal layer can be thinner, and the quality of the composite metal strips is also more stable.

[0080] The specific implementation method of the composite metal strip continuous production method is described below in conjunction with the composite metal strip continuous production equipment of this embodiment.

[0081] The continuous production method of the composite metal strip of this embodiment includes:

[0082] An extrusion coating step, in which a metal layer is extruded and coated on at least one side of the substrate 1 by using an extrusion roller group;

[0083] In the extrusion coating process, molten metal material is added to the feed side of the two extrusion rollers 3; the two extrusion rollers 3 are driven to rotate so that the tangential rate of the extrusion rollers 3 is equal to the rate of the substrate 1 passing through between the two extrusion rollers 3, and the molten metal material is extruded and coated on the substrate 1 by the extrusion rollers 3 to form a metal layer. Then, the cooling device arranged on the discharge side of the two extrusion rollers 3 is used to cool and shape the metal layer according to the set cooling rate to obtain a composite metal strip 2.

[0084] Furthermore, when the substrate 1 and one of the extrusion rollers 3 are always in contact, molten metal material is added to the side of the substrate 1 facing the other extrusion roller 3, and a metal layer is extruded and coated on one side of the substrate 1; when extrusion gaps are provided between the substrate 1 and the two extrusion rollers 3, molten metal material is added to both sides of the substrate 1, and metal layers are extruded and coated on both sides of the substrate 1.

[0085] In this embodiment, an extrusion gap is provided between the substrate 1 and the two extrusion rollers 3, and the same molten metal material is continuously added to both sides of the substrate 1, and metal layers of the same molten metal material are extruded and coated on both sides of the substrate 1; or different molten metal materials are continuously added to both sides of the substrate 1, and metal layers of different molten metal materials are extruded and coated on both sides of the substrate 1.

[0086] When the axes of the two squeezing rollers 3 of this embodiment are located on the same horizontal plane, the upper side of the two squeezing rollers 3 is the feeding side, and the substrate 1 of this embodiment passes between the two squeezing rollers 3 along the vertical downward direction.

[0087] Further, the extrusion gaps between the substrate 1 and the two extrusion rollers 3 are equal, or the difference between the extrusion gaps between the substrate 1 and the two extrusion rollers 3 is within a set range. In this embodiment, the extrusion gaps between the substrate 1 and the two extrusion rollers 3 are equal, that is, metal layers of equal thickness are extrusion-coated on both sides of the substrate 1.

[0088] Furthermore, when adding materials, molten metal materials can be directly added to the feed side of the two extrusion rollers 3, and the molten metal materials can be kept in a molten state by using a heating device arranged on the feed side of the two extrusion rollers; or, metal particles or metal powders can be sprayed above the two extrusion rollers 3, and the metal particles or metal powders can be melted by using a heating device arranged on the feed side of the two extrusion rollers to obtain molten metal materials. In this embodiment, a feed pump 4 is arranged to directly add molten metal above the two extrusion rollers 3. Of course, a powder spraying device can also be used to spray metal particles or metal powders above the two extrusion rollers 3, and the principle is equivalent and will not be repeated.

[0089] Further, the substrate 1 may be a mesh foil or an array of through holes may be provided on the substrate 1. If the substrate 1 is a mesh foil, the metal layers on both sides of the substrate 1 in this embodiment are connected together through the mesh holes on the substrate 1. If the substrate 1 is provided with through holes in an array, the metal layers on both sides of the substrate 1 in this embodiment are connected together through the through holes on the substrate 1. The strength of the bonding force between the metal layer and the substrate 1 can be effectively enhanced. Specifically, the substrate 1 is made of, but not limited to, a copper strip, an aluminum strip, a steel strip, a nickel strip, a silver strip, a gold strip, or a strip composite of a metal material and a non-metallic material, which will not be described again.

[0090] Further, the molten metal material is but not limited to metal lithium, metal sodium, metal potassium, metal magnesium, metal calcium, metal zinc, metal aluminum or metal silver; or the molten metal material is but not limited to an alloy formed by at least two proportions of metal lithium, metal sodium, metal potassium, metal magnesium, metal calcium, metal zinc, metal aluminum and metal silver. Specifically, according to different situations, non-metals can also be doped in the metal. And according to the different characteristics of different metals, the metal can also be extruded and coated on the side of the substrate 1 under a set atmosphere. Of course, further, the same metal can be continuously added to both sides of the substrate, and metal layers of the same metal can be extruded on both sides of the substrate; or different metals can be continuously added to both sides of the substrate, and metal layers of different metals can be extruded on both sides of the substrate, that is, the continuous production method of the composite metal strip of the present invention can be extruded on both sides of the substrate, or according to needs, metal layers of different metals can be extruded on both sides of the substrate 1. The metal of this embodiment uses metallic lithium. According to the use situation, the metallic lithium can be doped with materials such as rare earth, carbon, graphite and graphene, which will not be repeated.

[0091] Furthermore, the mass of metal added per unit time is:

[0092] q=vlhρ+q0

[0093] Where q is the mass of metal added per unit time;

[0094] v is the velocity of the substrate;

[0095] l is the width of the metal layer extruded on the substrate;

[0096] h is the thickness of the metal layer;

[0097] ρ is the density of the metal;

[0098] q0 is the metal loss per unit time during the extrusion process, such as a small amount of metal adhering to the surface of the extrusion roller 3.

[0099] Furthermore, the conveying rate of the substrate 1 is 0-400km / h, and the conveying rate of the substrate 1 is adjusted according to different metal layers, so as to ensure that the metal layer can be smoothly formed. In this embodiment, the spacing between the two side surfaces of the substrate 1 and the two extrusion rollers 3 is equal, and metal layers of the same thickness can be extruded on both sides of the substrate 1. Of course, when producing certain composite metal strips, the spacing between the two side surfaces of the substrate 1 and the two extrusion rollers 3 can also be set to be unequal, that is, metal layers of different thicknesses are extruded on both sides of the substrate 1. Furthermore, the spacing between the two side surfaces of the substrate 1 and the two extrusion rollers 3 is greater than or equal to 0.02um, that is, the thickness of the metal layer is greater than or equal to 0.02um, and the spacing between the two side surfaces of the substrate 1 and the two extrusion rollers 3 can be set according to actual requirements, so that metal layers of different thicknesses can be extruded.

[0100] Furthermore, the cooling device cools the metal layer to a set temperature range according to a set cooling curve. On the one hand, the cooling device needs to cool the metal layer quickly to prevent the metal that is still in a molten state and is extruded onto the substrate 1 from falling off the substrate 1. On the other hand, the cooling rate can be adjusted to obtain the desired crystal form in the metal layer, which will not be repeated.

[0101] Furthermore, the continuous production method of the composite metal strip of the present embodiment also includes a finishing process, using at least one group of finishing rollers to roll the composite metal strip or laser finishing equipment in sequence, so that the thickness of the metal layer reaches a set thickness. Specifically, the composite metal strip can be cooled and shaped by a cooling device, restored to room temperature under natural conditions, and then finished. Specifically, the present embodiment uses a finishing roller group to finish the composite metal strip 2. In the finishing process, the metal layer is kept within a set temperature range that is conducive to its finishing and forming. For example, if the metal of the present embodiment uses metallic lithium, the metallic lithium can be kept at a higher temperature to soften it, and then it can be finished, which has a better effect.

[0102] Furthermore, among the two finishing rollers in the last group of finishing rollers, at least one finishing roller is provided with a rolling needle for rolling holes on the corresponding metal layer of the composite metal strip. Alternatively, the continuous production method of composite metal strips in this embodiment also includes a hole rolling process after the finishing process, and the hole rolling process uses a rolling roller or a pressing plate to process holes on at least one metal layer of the composite metal strip. This embodiment uses a method of processing holes on the composite metal strip by arranging rolling needles on the finishing rollers in the last group of finishing rollers. Specifically, the holes rolled on the metal layer are nanoscale holes, the pore size of the nanoscale holes is greater than or equal to 1nm and less than or equal to 1um, and the pore spacing between the nanoscale holes satisfies:

[0103] L≤kδ

[0104] Wherein, L is the pore spacing of the nanoscale pores; k is a coefficient, and k ≥ 1; δ is the thickness of the diffusion control layer.

[0105] Furthermore, the thickness of the diffusion control layer is:

[0106]

[0107] Wherein, δ is the thickness of the diffusion control layer; D is the diffusion coefficient; and t is the time.

[0108] By limiting the pore spacing between nanoscale pores by the thickness of the diffusion control layer, the effects of mass transfer or diffusion control can be eliminated or reduced.

[0109] Furthermore, before the composite metal strip is rolled up, an isolation film 20 is compounded on at least one side of the composite metal strip 2 to prevent two adjacent layers of the composite metal strip from sticking together. In this embodiment, the isolation film 20 is compounded only on the lower side of the composite metal strip 2. For some soft metal layers, it can prevent the metal layers from sticking together.

[0110] Example 2

[0111] like Figure 4 The figure is a schematic diagram of the structure of the composite metal strip continuous production equipment embodiment 2 of the present invention. The composite metal strip continuous production equipment of this embodiment includes:

[0112] Unwinding mechanism: comprising an unwinding roller 16, used for continuously unwinding the substrate 1;

[0113] Extrusion molding device: used for extruding a metal layer on at least one side of the substrate 1 to obtain a composite metal strip 2;

[0114] The winding mechanism includes a winding roller 17 for winding the prepared composite metal strip 2;

[0115] The extrusion molding device includes an extrusion roller group, which includes two extrusion rollers 3 whose axes are parallel to each other; a feeding device for adding molten metal material is provided on the feeding side of the two extrusion rollers 3;

[0116] The feeding side of the extrusion roller group is provided with a high temperature zone for keeping the molten metal material in a molten state, and the discharging side of the extrusion roller group is provided with a cooling zone for cooling and shaping the composite metal strip 2;

[0117] A guide mechanism for allowing the substrate 1 to pass between the two squeezing rollers 3 is provided between the unwinding mechanism and the rewinding mechanism. The guide mechanism includes a plurality of guide rollers 19 .

[0118] Furthermore, a roll gap adjusting mechanism for adjusting the roll gap is provided between the two extrusion rollers 3, which can adjust the roll gap width between the two extrusion rollers 3, thereby controlling the forming thickness of the metal layer.

[0119] Further, when the substrate 1 and one of the extrusion rollers 3 are always in contact, the feeding device includes a feeding mechanism for adding molten metal material to the side of the substrate 1 facing the other extrusion roller; when an extrusion gap is provided between the substrate 1 and the two extrusion rollers 3, the feeding device includes two feeding mechanisms for adding molten metal material to both sides of the substrate. In this embodiment, the substrate 1 and one of the extrusion rollers 3 are always in contact.

[0120] Furthermore, the axes of the two extrusion rollers 3 of this embodiment are located on the same horizontal plane, and the upper side of the two extrusion rollers 3 is the feeding side. The guide mechanism of this embodiment guides the substrate 1 to always keep in contact with one of the extrusion rollers 3, and an extrusion gap is provided between the substrate 1 and the other extrusion roller 3, that is, the metal layer is extruded only on one side of the substrate 1.

[0121] Further, the feeding mechanism includes a feeding pump 4 for conveying molten metal material into the high temperature zone, or the feeding mechanism includes a powder spraying device for conveying metal particles or metal powder into the high temperature zone, and the feeding device also includes a melting heating mechanism arranged in the high temperature zone and used to melt the metal particles or metal powder and form molten metal material. The feeding mechanism of this embodiment includes a feeding pump 4 for conveying molten metal into the high temperature zone, and the feeding pump 4 is provided with a nozzle 4a for conveying molten metal into the high temperature zone.

[0122] Furthermore, a drainage device for draining the molten metal material to the top of the two extrusion rollers 3 is provided in the high temperature zone. The drainage device of this embodiment includes a drainage plate 5 provided in the high temperature zone. Specifically, the drainage plate 5 of this embodiment is provided as one piece, and the drainage plate 5 is used to drain the molten metal material to the extrusion gap.

[0123] Furthermore, a cold air device is provided in the cooling zone. The cold air device includes a cold air unit provided corresponding to the side of the substrate 1 provided with the metal layer. In the present embodiment, one cold air unit is provided. Of course, the cold air unit can also be provided as two units respectively located on both sides of the substrate 1, which will not be described again. The cold air unit in the present embodiment includes an air guide plate 8; the outer side of the air guide baffle plate facing away from the substrate 1 is provided with a cold air channel 8a for blowing the cooling medium on the discharge side facing the extrusion roller group, and a reflux channel 8b for reflux of the cooling medium is formed between the air guide baffle plate and the substrate 1, such as Figure 2 As shown; or, a cold air channel for blowing the cooling medium on the discharge side of the extrusion roller group is formed between the air guide baffle and the substrate 1, and a reflux channel for reflux of the cooling medium is provided on the outer side of the air guide baffle facing away from the substrate 1, such as Figure 3 Specifically, an air inlet gap 9 is provided between the air guide plate 8 and the squeezing roller 3, and the air inlet gap is connected to the cold air channel and the return air channel.

[0124] The substrate 1 of this embodiment is made of, but not limited to, copper strip, aluminum strip, steel strip, nickel strip, silver strip, gold strip or a strip composite of metal material and non-metal material. The substrate 1 is made of a mesh foil or strip with through holes arranged in an array, and the metal layer composited on one side of the substrate 1 is embedded in the mesh or through holes to increase the strength of the bonding force.

[0125] Of course, the substrate 1 of this embodiment can also be, but not limited to, release paper. When in use, the release paper in the composite metal strip can be peeled off from the metal layer to obtain a metal strip. Specifically, the release paper can be implemented using a variety of existing release films. The release paper of this embodiment can be a release film combination for processing battery-grade lithium strips described in the Chinese patent application with publication number CN107236144A, which will not be repeated.

[0126] The other implementations of this embodiment are the same as those of Embodiment 1 and are not described one by one.

[0127] The specific implementation method of the composite metal strip continuous production method is described below in conjunction with the composite metal strip continuous production equipment of this embodiment.

[0128] The continuous production method of the composite metal strip of this embodiment includes:

[0129] An extrusion coating step, in which a metal layer is extruded and coated on at least one side of the substrate 1 by using an extrusion roller group;

[0130] In the extrusion coating process, molten metal material is added to the feed side of the two extrusion rollers 3; the two extrusion rollers 3 are driven to rotate so that the tangential rate of the extrusion rollers 3 is equal to the rate of the substrate 1 passing through between the two extrusion rollers 3, and the molten metal material is extruded and coated on the substrate 1 by the extrusion rollers 3 to form a metal layer. Then, the cooling device arranged on the discharge side of the two extrusion rollers 3 is used to cool and shape the metal layer according to the set cooling rate to obtain a composite metal strip 2.

[0131] Further, when the substrate 1 and one of the extrusion rollers 3 are always in contact, molten metal material is added to the side of the substrate 1 facing the other extrusion roller 3, and a metal layer is extruded and coated on one side of the substrate 1; when an extrusion gap is provided between the substrate 1 and the two extrusion rollers 3, molten metal material is added to both sides of the substrate 1, and a metal layer is extruded and coated on both sides of the substrate 1. In this embodiment, the substrate 1 and one of the extrusion rollers 3 are always in contact, that is, molten metal material is added only to the side of the substrate 1 facing the other extrusion roller 3, and a metal layer is extruded and coated on one side of the substrate 1. The axes of the two extrusion rollers 3 in this embodiment are located on the same horizontal plane, and the upper side of the two extrusion rollers 3 is the feed side.

[0132] Furthermore, when adding materials, molten metal materials can be directly added to the feed side of the two extrusion rollers 3, and the molten metal materials can be kept in a molten state by using a heating device arranged on the feed side of the two extrusion rollers; or, metal particles or metal powders can be sprayed above the two extrusion rollers 3, and the metal particles or metal powders can be melted by using a heating device arranged on the feed side of the two extrusion rollers to obtain molten metal materials. In this embodiment, a feed pump 4 is arranged to directly add molten metal above the two extrusion rollers 3. Of course, a powder spraying device can also be used to spray metal particles or metal powders above the two extrusion rollers 3, and the principle is equivalent and will not be repeated.

[0133] Further, the substrate 1 can be made of a mesh foil or an array of through holes can be provided on the substrate 1. If the substrate 1 is made of a mesh foil, the metal layer provided on the side of one side of the substrate 1 in this embodiment is embedded in the mesh of the substrate 1. If the substrate 1 is provided with through holes in an array, the metal layer provided on the side of one side of the substrate 1 in this embodiment is embedded in the through hole of the substrate 1. The strength of the bonding force between the metal layer and the substrate 1 can be effectively enhanced. Specifically, the substrate 1 is made of but not limited to copper strip, aluminum strip, steel strip, nickel strip, silver strip, gold strip or a strip composite of metal material and non-metallic material. Of course, the substrate 1 of this embodiment can also be made of but not limited to release paper. When used, the release paper in the composite metal strip can be peeled off from the metal layer to obtain a metal strip. Specifically, the release paper can be realized by using a variety of existing release films. The release paper of this embodiment can be a release film combination for processing battery-grade lithium strips recorded in the Chinese patent application with publication number CN107236144A, which will not be repeated.

[0134] The other implementations of this embodiment are the same as those of Embodiment 1 and are not described one by one.

[0135] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A composite metal strip continuous production equipment, characterized in that: include: Unwinding mechanism: used for continuously unwinding the substrate (1); An extrusion molding device: used for extruding a metal layer on at least one side of a substrate (1) to obtain a composite metal strip (2); A winding mechanism: used for winding the prepared composite metal strip (2); The extrusion molding device comprises an extrusion roller group, wherein the extrusion roller group comprises two extrusion rollers whose axes are parallel to each other; a feeding device for adding molten metal material is provided on the feeding side of the two extrusion rollers; The feed side of the extrusion roller group is provided with a high temperature zone for keeping the molten metal material in a molten state, and the discharge side of the extrusion roller group is provided with a cooling zone for cooling and shaping the composite metal strip (2); A guide mechanism is provided between the unwinding mechanism and the rewinding mechanism for allowing the substrate (1) to pass between the two squeezing rollers (3); A cold air device is provided in the cooling zone; the cold air device comprises a cold air unit arranged corresponding to the side of the substrate (1) provided with the metal layer, and the cold air unit comprises an air guide plate (8); the outer side of the air guide plate facing away from the substrate (1) is provided with a cold air channel for blowing cooling medium on the discharge side of the extrusion roller group, and a reflux channel for reflux of cooling medium is formed between the air guide plate and the substrate (1); or, a cold air channel for blowing cooling medium on the discharge side of the extrusion roller group is formed between the air guide plate and the substrate (1), and a reflux channel for reflux of cooling medium is formed on the outer side of the air guide plate facing away from the substrate (1); an air inlet gap is provided between the air guide plate and the extrusion roller, and the air inlet gap connects the cold air channel and the reflux channel; A finishing zone is provided between the extrusion forming device and the winding mechanism, and at least one group of finishing rollers is arranged in the finishing zone, and each group of the finishing rollers includes two corresponding finishing rollers; at least one of the two finishing rollers in the last group of the finishing rollers is provided with a rolling needle for rolling holes on the corresponding metal layer of the composite metal strip; the rolling needle is a nanometer-scale rolling needle, and the outer diameter of the rolling needle is greater than or equal to 1nm and less than or equal to 1um; the spacing between two adjacent rolling needles satisfies: L≤kδ Wherein, L is the pore spacing of nanoscale pores; k is a coefficient, and k ≥ 1; δ is the thickness of the diffusion control layer; The thickness of the diffusion control layer is: Wherein, δ is the thickness of the diffusion control layer; D is the diffusion coefficient; t is the time; The mass of the metal material added by the feeding device to the feeding side of the two extrusion rollers per unit time is: q=vlhρ+q0 Among them, q is the mass of metal material added per unit time; v is the transport rate of the substrate; l is the width of the metal layer extruded on the substrate; h is the thickness of the metal layer; ρ is the density of the metal; q0 is the metal loss per unit time during the extrusion process.

2. The composite metal strip continuous production equipment according to claim 1, characterized in that: A roll gap adjusting mechanism for adjusting the roll gap is arranged between the two squeezing rolls.

3. The composite metal strip continuous production equipment according to claim 1, characterized in that: When the substrate is always in contact with one of the squeezing rollers, the feeding device includes a feeding mechanism for feeding metal material to the side of the substrate facing the other squeezing roller; When an extrusion gap is respectively provided between the substrate and the two extrusion rollers, the feeding device comprises two feeding mechanisms respectively used for feeding metal materials to two sides of the substrate.

4. The composite metal strip continuous production equipment according to claim 3, characterized in that: When the axes of the two squeezing rollers are located on the same horizontal plane, the upper sides of the two squeezing rollers are the feeding side.

5. The composite metal strip continuous production equipment according to claim 4, characterized in that: When an extrusion gap is respectively provided between the substrate and the two extrusion rollers, the guide mechanism guides the substrate to pass through between the two extrusion rollers in a vertical downward direction.

6. The composite metal strip continuous production equipment according to claim 5, characterized in that: The guide mechanism guides the substrate and makes the extrusion gap between the substrate and the two extrusion rollers equal, or makes the difference between the extrusion gap between the substrate and the two extrusion rollers within a set range.

7. The composite metal strip continuous production equipment according to claim 3, characterized in that: The feeding mechanism comprises a feeding pump (4) for conveying molten metal material into the high temperature zone, or the feeding mechanism comprises a powder spraying device for conveying metal particles or metal powder into the high temperature zone, and the feeding device also comprises a melting heating mechanism arranged in the high temperature zone and used to melt the metal particles or metal powder to form molten metal material.

8. The composite metal strip continuous production equipment according to claim 1, characterized in that: The high temperature zone is provided with a drainage device for diverting the molten metal material to the feed side of the two extrusion rollers (3).

9. The composite metal strip continuous production equipment according to claim 8, characterized in that: The drainage device comprises a drainage plate (5) arranged in the high temperature zone.

10. The composite metal strip continuous production equipment according to claim 9, characterized in that: The guide plates (5) are provided in two pieces, and the two guide plates (5) are respectively located below the feeding device.

11. The composite metal strip continuous production equipment according to claim 10, characterized in that: A heating zone (6) for heating is provided on the opposite sides of the two guide plates (5), and a constant temperature zone (7) is formed between the two guide plates (5).

12. The composite metal strip continuous production equipment according to claim 1, characterized in that: The cold air units are provided in two and are respectively located on both sides of the substrate (1).

13. The composite metal strip continuous production equipment according to claim 12, characterized in that: The two air guide plates (8) are symmetrically arranged relative to the symmetric planes of the two squeezing rollers (3).

14. The composite metal strip continuous production equipment according to claim 1, characterized in that: It also includes a scraper (10) for scraping off the molten metal material attached to the extrusion roller (3).

15. The composite metal strip continuous production equipment according to claim 14, characterized in that: A collecting box (11) is provided below the scraper (10).

16. The composite metal strip continuous production equipment according to any one of claims 1 to 15, characterized in that: The substrate (1) is made of copper strip, aluminum strip, steel strip, nickel strip, silver strip, gold strip or a strip composite of metal material and non-metal material; or the substrate is made of release paper.

17. The composite metal strip continuous production equipment according to claim 16, characterized in that: The substrate (1) is a mesh foil material or a strip material having through holes arranged in an array.

18. The composite metal strip continuous production equipment according to any one of claims 1 to 15, characterized in that: The metal material is lithium metal, sodium metal, potassium metal, magnesium metal, calcium metal, zinc metal, aluminum metal or silver metal; or the metal material is an alloy formed by a proportion of at least two of lithium metal, sodium metal, potassium metal, magnesium metal, calcium metal, zinc metal, aluminum metal and silver metal.

19. The composite metal strip continuous production equipment according to claim 1, characterized in that: The finishing area is provided with a laser finishing device for finishing the composite metal strip.

20. The composite metal strip continuous production equipment according to claim 19, characterized in that: Between two adjacent finishing roller groups, the gap between the rollers of the finishing roller group on the side close to the extrusion forming device is larger than the gap between the rollers of the finishing roller group on the side close to the winding mechanism.

21. The composite metal strip continuous production equipment according to claim 1, characterized in that: A heat preservation device (13) for maintaining the rolling temperature within a set range is provided in the finishing area.

22. The composite metal strip continuous production equipment according to claim 1, characterized in that: It also includes a trimming device, which is arranged in the finishing area or between the finishing area and the winding mechanism.

23. The composite metal strip continuous production equipment according to claim 1, characterized in that: A film laminating mechanism for laminating an isolation film (20) onto at least one side surface of the composite metal strip (2) is provided at the front end of the winding mechanism.

24. The composite metal strip continuous production equipment according to claim 23, characterized in that: The film composite mechanism comprises a film unwinding mechanism (21) for unwinding an isolation film (20) and a composite roller group (22) for composite the composite metal strip (2) and the isolation film (20).

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