Manufacturing equipment of composite belt

Abstract

The utility model provides manufacturing equipment of a composite belt. Comprising a conveying system used for continuously conveying base materials; the coating mechanism comprises a die head, and the die head is used for coating molten liquid on the continuously conveyed base material under the protective atmosphere; the molten liquid conveying system is used for conveying molten liquid to the die head under the protective atmosphere; the cooling and shaping mechanism is used for cooling and shaping the coated base material; the calendaring mechanism is used for calendaring the cooled and shaped base material; and the coating mechanism, the cooling and shaping mechanism and the calendering mechanism are sequentially arranged along the conveying direction of the base material. According to the utility model, the molten liquid is conveyed to the die head through the molten liquid conveying system under shielding gas; the continuously conveyed base material is coated by the die head under the combined action of the protective gas and a stirring device in the die head; the composite belt with a plurality of continuous and uniform coating layers is prepared through the further action of cooling shaping and a calendaring mechanism; and the practical value is high.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the battery production technical field, more particularly to a kind of manufacturing equipment of composite tape. BACKGROUND

[0002] During the first charge-discharge process of lithium-ion batteries and sodium-ion batteries, the organic electrolyte will undergo reduction decomposition on the surface of the negative electrode such as graphite, forming a solid electrolyte interface film (SEI). This process not only consumes a large amount of lithium, resulting in a low initial cycle coulombic efficiency (ICE), but also reduces the capacity, energy density, and lifespan of the battery. To address this issue, researchers and engineers have been seeking effective solutions.

[0003] Pre-lithiation is an effective method to improve the energy density of lithium-ion batteries. Pre-lithiation refers to introducing an additional lithium source into the positive or negative electrode material of the battery before assembly, to compensate for the irreversible loss of lithium during the first cycle.

[0004] Under normal circumstances, we refer to the material that needs to be coated with molten metal as the substrate; the pre-lithiation method mainly includes sprinkling lithium powder on the surface of the substrate and rolling composite with lithium foil or lithium metal composite tape and the substrate. However, the existing lithium powder and rolling composite scheme has some significant problems. When using lithium powder for pre-lithiation, due to the highly active chemical properties of metallic lithium, the powder material has a large specific surface area, which significantly increases the risk of lithium-ion battery combustion and explosion. In addition, the uneven distribution of lithium powder inside the battery can easily lead to local lithium excess, further increasing the safety risk.

[0005] The method of using lithium foil or lithium metal composite tape for rolling composite can avoid the dispersion problem of lithium powder, but also has its own limitations. The current commercial lithium foil is mainly produced through extrusion, rolling, and surface passivation. Thin metal lithium foil with a thickness of 20-100 μm can be prepared by multi-roller rolling, but it is difficult to obtain thinner thickness due to the high viscosity and poor mechanical processing properties of metallic lithium at room temperature. After the conventional lithium strip is assembled into a lithium battery, there may be residual lithium layer, which poses a safety hazard. In addition, since the negative electrode sheet of the lithium battery is usually wide coated, leaving a blank in the middle as a current collector, it is necessary to first divide the negative electrode sheet into multiple parts before rolling the lithium strip. This process not only reduces production efficiency, but also due to the discontinuity of the lithium layer, uniform pre-lithiation cannot be achieved.

[0006] Some researchers try to alleviate the problem that the existing lithium layer covers the entire composite surface by setting a continuous lithium coating layer on both sides of the substrate, with intermittent lithium coating layers in between. This method improves the uniformity of the lithium layer to some extent, but still has obvious shortcomings. Because only part of the area on the negative electrode sheet has a lithium layer, the area without a lithium layer cannot be pre-lithiated, which will cause inconsistent battery performance. In addition, uneven thickness of the electrode sheet will also cause equipment running deviation and other problems, affecting the manufacturing quality and consistency of the battery.

[0007] Therefore, in view of the above problems, the researchers believe that how to use molten metal liquid to continuously and uniformly coat the substrate is the focus of the utility model, and at the same time, for the obvious difference between lithium and copper foil melting point, how to further improve the wettability between the molten metal liquid and the substrate, and realize the preparation of ultra-thin lithium metal by coating molten lithium liquid metal on the surface of the copper foil is also a problem we need to further consider. Utility model content

[0008] The utility model fully considers how to ensure continuous and uniform coating of multiple lithium strips on the substrate with high precision and high efficiency, and discloses a manufacturing equipment of composite tape. The manufacturing equipment has high industrial application value, and especially provides good operating conditions for improving the electrochemical performance of battery pre-lithiation.

[0009] The utility model is implemented through the following technical solutions:

[0010] In a first aspect, the utility model provides a manufacturing equipment of composite tape, and the manufacturing equipment of composite tape comprises:

[0011] A conveying system is used for continuously conveying the substrate;

[0012] A coating mechanism comprises a die head, and the die head is used for molten liquid coating of the continuously conveyed substrate under a protective atmosphere;

[0013] A molten liquid transmission system is used for conveying the molten liquid to the die head under a protective atmosphere.

[0014] As a further scheme, the die head has two parts of an upper die head and a lower die head; the upper die head and the lower die head are combined to form a hollow liquid storage tank;

[0015] The liquid storage tank has a rotatable stirring device inside;

[0016] The stirring device is also provided with detachable sealing devices at both ends; at least one of the sealing devices is provided with a high-pressure protective gas inlet connected with the liquid storage tank.

[0017] As a further scheme, the upper die head and the lower die head are respectively provided with ports at end positions of the liquid storage grooves, the inner wall of the port is provided with an inner wall groove, the stirring device is provided with a groove matched with the inner wall groove for fixing the stirring device, and the outer wall of the port is provided with an outer groove for fixing the sealing device.

[0018] Further, the sealing device further comprises a sealing cover plate and a cover plate protruding part, the sealing cover plate has a larger diameter than the cover plate protruding part and is integrally arranged with the cover plate protruding part, and the cover plate protruding part is sealingly inserted into the outer groove of the outer wall of the port.

[0019] Further, the sealing cover plate is provided with the high-pressure protective gas inlet, and the port is provided with an air inlet channel corresponding to the high-pressure protective gas inlet, the air inlet channel is communicated with the inner wall groove, and the air inlet channel realizes air inlet of the liquid storage groove.

[0020] As a further scheme, the die head further comprises a gasket, the gasket is arranged in a region between the liquid storage groove and the edge of the die head, the gasket is provided with a gasket opening towards the edge of the die head, and the gasket opening realizes uniform distribution and discharge of the molten liquid; wherein the edge of the die head corresponding to one side of the gasket opening is the die head discharge port.

[0021] The die head further comprises a fine adjustment mechanism, the fine adjustment mechanism is arranged on the upper die head, and the die head further comprises a die head heating device.

[0022] Further, the gasket is provided with at least two positioning pins, and the positioning pins realize fixation of the gasket on the die head.

[0023] Further, the fine adjustment mechanism comprises an adjusting plate and at least two parallel arranged threaded rods, the adjusting plate is provided with threaded holes corresponding to the threaded rods, the threaded rods are connected with the adjusting plate through the threaded holes, the adjusting plate is arranged at a position relatively fixed with the upper die head, and the free end of the threaded rod acts on the upper die head to change the opening size of the die head discharge port by applying force to the upper die head.

[0024] As a further scheme, the coating mechanism further comprises a die head stopper, the die head stopper is movably arranged on one side of the die head, and the die head stopper is used for covering the die head when the die head is not coated to prevent liquid leakage of the die head.

[0025] Further, the die head stopper comprises a movable support and a stop plate, the stop plate is detachably arranged on the support and close to one side of the die head.

[0026] Further, the die head stopper further comprises a stopper heating device, the stopper heating device is detachably arranged on the support and away from one side of the die head.

[0027] Further, a waste liquid collecting groove is detachably arranged below the baffle.

[0028] As a further scheme, the molten liquid conveying system comprises a feeding and air exchange metering bin, a melting tank, a molten liquid storage tank, and a protective gas tank.

[0029] Further, one end of the protective gas tank is independently connected with the feeding and air exchange metering bin, the melting tank, and the molten liquid storage tank respectively, and the other end is connected with a high-pressure protective gas inlet on the die head.

[0030] Further, the molten liquid conveying system is further provided with a solution pump, and feeding of the die head is realized through the solution pump.

[0031] Further, the molten liquid conveying system further comprises a conveying pipe for sequentially connecting various parts of the molten liquid conveying system.

[0032] Further, the molten liquid conveying system further comprises a vacuum pump, and the vacuum pump is connected with the feeding and air exchange metering bin.

[0033] As some specific schemes, the manufacturing device can further have a substrate heating mechanism; the substrate heating mechanism is used for heating the substrate before coating; and the substrate heating mechanism is used for improving wettability of the molten lithium and enhancing combination of the molten lithium and the substrate.

[0034] Further, the substrate heating mechanism comprises an upper assembly and a lower assembly; the upper assembly and the lower assembly are combined to form a hollow chamber; a plurality of groups of rollers are arranged in the chamber; and the rollers are used for conveying the substrate and ensuring that the substrate can be uniformly heated during the heating process.

[0035] Further, the upper assembly and the lower assembly are provided with a substrate inlet and a substrate outlet along a conveying direction of the substrate at a combined contact part of the upper assembly and the lower assembly; and the substrate inlet and the substrate outlet are used for realizing that the substrate enters the substrate heating mechanism to be heated.

[0036] Further, the upper assembly and the lower assembly are respectively independently provided with a hot gas inlet and a hot gas outlet at two sides of the upper assembly and the lower assembly after being combined.

[0037] The specific arrangement positions of the hot gas inlet and the hot gas outlet are not limited in principle in the utility model; the skilled in the art can select and design according to actual needs; as some examples, the hot gas inlet can be arranged on the outside of the lower assembly, and the hot gas outlet can be arranged on the outside of the upper assembly.

[0038] Further, the substrate heating mechanism is further connected with a heating box; and the heating box is connected with the hot gas inlet of the substrate heating mechanism through a pipeline. The heating box is used for realizing heating of the gas, and then the heated gas enters the substrate heating mechanism to realize heating of the substrate.

[0039] The utility model disc not make the specific position of heating box limited, and the person skilled in the art can select and design according to actual needs, as some examples, the utility model connects heating box outside the base material heating mechanism, realizes the heating of base material.

[0040] As a further scheme, the manufacturing equipment of the composite tape further comprises a cooling and shaping mechanism and a calendering mechanism, the cooling and shaping mechanism is used for cooling and shaping the coated base material, and the calendering mechanism is used for calendering the cooled and shaped base material.

[0041] Further, the unwinding system comprises an unwinding shaft and at least one set of unwinding rolling rollers, the unwinding shaft is used for sleeving the base material, and the unwinding rolling rollers are arranged between the unwinding shaft and the coating mechanism and are used for realizing continuous feeding of the base material.

[0042] Further, the winding system is arranged behind the calendering mechanism along the base material conveying direction, comprises a winding shaft and at least one set of winding rolling rollers, and the winding rolling rollers are arranged between the winding shaft and the calendering mechanism.

[0043] As a further scheme, the cooling and shaping mechanism is arranged behind the coating mechanism along the base material conveying direction and is used for cooling and shaping the coated composite tape, and the cooling and shaping mechanism comprises at least one set of upper cooling rollers and lower cooling rollers which are coaxially arranged on the upper side and the lower side of the base material.

[0044] The calendering mechanism is arranged behind the cooling and shaping mechanism along the base material conveying direction, and the calendering mechanism comprises at least one set of calendering rollers which are coaxially arranged on the upper side and the lower side of the base material.

[0045] As a further scheme, the manufacturing equipment of the composite tape further comprises an encoding mechanism, the encoding mechanism is arranged between the calendering mechanism and the winding system, the encoding mechanism comprises at least one set of tension rollers which are coaxially arranged on the two sides of the base material, and the encoding mechanism further comprises an encoding rolling roller and an encoder.

[0046] The utility model has the characteristics and beneficial effects that:

[0047] (1) the manufacturing equipment of the utility model realizes continuous conveying of the base material through the winding and unwinding mechanism, ensures continuity and consistency in the coating process, and is favorable for realizing preparation of continuous and uniform composite tape.

[0048] (2) the utility model adopts a molten liquid conveying system to convey molten liquid to the die head, has high-precision control ability, ensures stability and continuity of the molten liquid in the conveying process, thereby improving the quality and performance of the composite tape.

[0049] (3) The base material heating device is further optimized, the base material is heated before coating, the contact angle of the metal molten liquid on the base material is reduced, the bonding strength of the coating layer and the base material is improved, the uniformity of the prepared composite strip is promoted, and different thicknesses or thinner metal coating layers can be prepared according to requirements.

[0050] (4) The die head has a built-in stirring device and is coated in a protective atmosphere, and the die head baffle covers the liquid outlet side of the die head; the problem of uneven coating caused by solidification and oxidation during the coating of the molten metal liquid can be effectively solved; the setting can enhance the adhesion between the coating layer and the base material, and can also control the thickness, width, number and other parameters of the coating layer; and provides a good operating environment for preparing a composite strip with multiple coating layers. In addition, the built-in stirring device can continuously stir the molten metal liquid to ensure the uniformity of the temperature and composition, thereby further improving the quality of the composite strip. The setting of the die head baffle not only prevents the overflow of the molten liquid and avoids the blockage of the molten liquid, but also reduces the interference of environmental factors on the coating process, and ensures the accuracy of the coating operation. Furthermore, the equipment of the utility model further cools and shapes the base material coated by the coating system, and performs calendering treatment; and the temperature and roll gap of the cooling roller and the extension roller are controlled to further ensure the flatness and thickness uniformity of the composite strip, and further eliminate surface scratches of the prepared composite strip.

[0051] (5) The manufacturing equipment of the utility model is simple to operate, can greatly improve production efficiency, reduce production cost, and realize continuous production of the composite strip. Through these technical solutions, the utility model not only solves the problems of uneven and discontinuous prelithiation in the prior art, but also significantly improves the performance of the battery. In addition, the manufacturing equipment provided by the utility model can also be applied to the coating of other metal molten liquids on the base material to prepare a composite strip with composite requirements, and has high industrial practical value. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the utility model, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description, and obviously, the drawings in the following description are only some embodiments of the utility model, and those skilled in the art can obtain other drawings according to these drawings without creating any creative labor.

[0053] Figure 1 is a molten liquid transmission system schematic diagram in the utility model embodiment 1-11;

[0054] Figure 2 is a manufacturing equipment schematic diagram of the composite strip in the utility model embodiment 1-10;

[0055] Figure 3 is a structure schematic view of the die in the embodiment 1-11 of the utility model;

[0056] Figure 4 is a partial structure schematic view of the fine adjustment structure in the embodiment 1-11 of the utility model;

[0057] Figure 5 is a partial structure schematic view of the die in the embodiment 1-11 of the utility model;

[0058] Figure 6 is a partial structure schematic view of the die in the embodiment 1-11 of the utility model;

[0059] Figure 7 is a structure schematic view of the die stopper in the embodiment 1-11 of the utility model;

[0060] Figure 8 is a structure schematic view of the gasket in the embodiment 1-11 of the utility model;

[0061] Figure 9 is a structure schematic view of the composite tape in the embodiment 1-11 of the utility model;

[0062] Figure 10 is a partial structure schematic view of the die in the embodiment 1-11 of the utility model;

[0063] Figure 11 is a manufacturing equipment schematic view of the composite tape in the embodiment 11 of the utility model;

[0064] Figure 12 is a structure schematic view of the base material heating mechanism in the embodiment 11 of the utility model;

[0065] Figure 13 is a partial structure schematic view of the base material heating mechanism in the embodiment 11 of the utility model;

[0066] Figure 14 is the contact angle when the metal molten liquid is coated on the base material in the embodiment 1 of the utility model;

[0067] Figure 15 is the contact angle when the metal molten liquid is coated on the base material heated by the base material heating mechanism in the embodiment 11 of the utility model.

[0068] Reference signs:

[0069] Base material 1; Coating layer 11;

[0070] Conveying system 2; Unwinding system 21; Winding system 22; Unwinding shaft 211; Unwinding rolling roller 212; Winding shaft 221; Winding rolling roller 222;

[0071] Coating mechanism 3; die head 31; upper die head 311; lower die head 312; liquid storage tank 313; stirring device 314; sealing device 315; high-pressure protective gas inlet 3151; stirring rod 3141; stirring shaft 3142; transmission device 3143; port 3131; inner wall groove 31311; channel 31312; outer groove 31313; sealing cover plate 3152; cover plate protrusion 3153; gas inlet channel 3154; gasket 316; gasket opening 3161; die head discharge port 317; positioning pin 3162; fine adjustment mechanism 318; adjustment plate 3181; threaded screw 3182; threaded hole 3183; fixing device 319; die head heating device 33; die head stopper 32; bracket 321; baffle 322; stopper heating device 323; waste liquid collection tank 324; die head inlet 331; die head backflow port 332;

[0072] Melt delivery system 4; charging and gas exchange metering bin 41; melting tank 42; melt storage tank 43; protective gas tank 44; solution pump 45; delivery pipe 46; vacuum pump 47;

[0073] Cooling and shaping mechanism 5; upper cooling roller 51; lower cooling roller 52;

[0074] Calendering mechanism 6; calendering roller 61;

[0075] Encoding mechanism 7; tension roller 71; encoding rolling roller 72; encoder 73;

[0076] Substrate heating mechanism 8; upper assembly 81; lower assembly 82; passing roller 83; substrate inlet 84; substrate outlet 85; hot gas inlet 86; hot gas outlet 87; heating box 88. DETAILED DESCRIPTION

[0077] In order to facilitate the understanding of the present application, the present application will be described more fully below, and an embodiment of the present application is given, but the scope of the present application is not limited thereby.

[0078] In the description of the present application, it should be noted that the terms "center", "middle", "upper", "lower", "left", "right", "inner", "outer", "top", "bottom", "side", "vertical", "horizontal" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0079] The utility model discloses personnel have carried out new prelithiation technical research, in order to solve the problem that the lithium powder or lithium metal composite band is used to the substrate 1 of prelithiation needs to carry out composite band preparation research, and easy to cause lithium excess, lithium layer is discontinuous and prelithiation uneven etc. when using the lithium powder or lithium metal composite band in the prior art, it is found through the utility model research that using the molten liquid is more convenient, controllable to the coating of substrate 1, and it can be expected to alleviate the problem of prelithiation discontinuity or unevenness. However, as a kind of fluid, the flowability, uniformity, easy oxidizability of molten liquid when coating substrate 1 are the key points that the utility model researchers need to explore and research. Based on this, the utility model carries out new prelithiation technology, proposes a kind of preparation equipment and manufacturing method of composite band, and it is expected to prepare the composite band with multiple continuous and uniform lithium layers simultaneously.

[0080] With reference to Figures 1-13 The utility model provides a kind of composite band;The composite band includes substrate 1 and coating layer 11;The coating layer 11 is located substrate 1;The coating layer 11 is continuously arranged along the length direction of substrate 1, and is interval setting in the width direction of substrate 1;The thickness of the coating layer 11 is selected from 0.1~100 μm.

[0081] Specifically, the interval distance of the coating layer 11 is consistent with the distance between every two gasket openings 3161 of the gasket 316 of the die head 31, and the thickness of the coating layer 11 is consistent with the thickness of each gasket opening 3161.

[0082] The composite tape prepared by the utility model has continuous and uniform coating layer 11, and preparation of multiple coating layers 11 can be simultaneously realized in the width direction of the base material 1; the interval distance of the coating layer 11 can be adjusted according to requirements. In addition, on the basis of realizing continuity and uniformity, the thickness of the composite tape provided by the utility model can reach 0.1 mu m at the lowest, and the thickness can be regulated and controlled, so that customization according to requirements is facilitated; thereby, the use amount of metal is significantly reduced, and the performance and safety of the battery are ensured. For example, when a graphite negative electrode, a negative electrode with less silicon carbon content or a negative electrode sheet with a relatively thin thickness is used, only 1-2 mu m of lithium supplement amount is required; and the rolling process of the composite tape mainly using lithium tape on the market can only realize a thickness of about 5 mu m, and it is difficult to roll and prepare a relatively thin lithium tape due to the strong ductility of lithium metal and the soft material, and the lithium tape is prone to breakage; when the coating layer prepared by the utility model is taken as an example of lithium and its alloy or a conductive agent composite layer, the thickness can be 3 mu m, 7 mu m, 14 mu m or 17 mu m and the like; and the coating layer with a relatively thin thickness of 0.1 mu m, 2 mu m and the like can also be prepared by regulating and controlling the equipment. The utility model provides a more efficient and safe solution to the problems of overcoating, discontinuity and unevenness of the lithium layer, and the need for multiple segmentation of the negative electrode sheet for calendering prelithiation; through the composite tape of the utility model, uniform prelithiation of the battery negative electrode material can be realized, so that the first coulomb efficiency of the battery is improved, the irreversible loss of lithium is reduced, the cycle stability of the battery is enhanced, and the service life of the battery is prolonged; and the composite tape can flexibly adapt to the requirements of different battery designs, and provides a larger design space for battery manufacturing.

[0083] As some specific solutions, the thickness of the coating layer 11 is preferably 0.1-5 mu m;

[0084] Further, the thickness of the coating layer 11 is preferably 0.1-3 mu m.

[0085] The utility model does not specially limit the material of the base material 1, and when the battery is prelithiated, the base material 1 is selected from one or more of a metal foil, a lithium battery positive electrode sheet, a lithium battery negative electrode sheet, a sodium battery positive electrode sheet or a sodium battery negative electrode sheet.

[0086] Further, the metal foil is selected from a metal-containing foil; as some specific examples: the metal-containing foil is selected from one or more of copper, aluminum, nickel, tin metal foil; or one or more non-metallic elements selected from carbon, silicon, boron and phosphorus are combined with one or more metal elements selected from copper, aluminum, nickel and tin to form a metal-containing foil.

[0087] Take the preparation of lithium composite belt by pre-lithiation as an example; after the base material is coated with molten lithium by using the device, on the one hand, the composite belt prepared by coating the base material with molten lithium can be directly coated with active material to prepare a battery pole piece for use; on the other hand, the base material can also be used as a transfer belt; after the preparation of the composite belt by coating the base material with molten lithium is completed; the lithium belt on the composite belt is separately transferred down, and is transferred to a pole piece by calendering treatment or the like, and the base material can be repeatedly used for coating and transferring of molten lithium.

[0088] As some specific solutions, the coating layer 11 is selected from a metal coating layer.

[0089] Further, the metal coating layer is selected from one or more metals or alloys thereof selected from potassium, sodium, indium, lithium, zinc, lead, silicon, tin and a metal conductive additive composite.

[0090] Further, the metal conductive additive is selected from one or more of carbon black, conductive graphite, carbon fiber, carbon nanotube, graphene, conductive polymer and metal conductive agent; and the proportion of the metal conductive additive is selected from 0.01-50%.

[0091] As some specific solutions, the metal coating layer is preferably selected from one or more of lithium and sodium.

[0092] In the preparation of the composite belt according to the present application, in order to further improve the bonding strength between the coating layer and the base material and avoid oxidation of the metal molten liquid, an additive can also be added to the metal molten liquid or the surface of the base material; the additive can include a metal antioxidant or a flux; wherein the metal antioxidant can be selected from phosphate (for example, sodium dihydrogen phosphate, sodium phosphite, sodium citrate, etc.), silicate (for example, sodium silicate, calcium silicate, etc.), borate (for example, potassium borate, sodium borate, etc.), organic metal antioxidant (for example, organic tin, organic cobalt, etc.); and the flux can be selected from one or more of an organic solvent, rosin resin and a derivative thereof.

[0093] The manufacturing equipment is especially suitable for preparation of lithium composite strips and sodium composite strips, and can effectively solve the problems of serious bead condensation, large surface tension and easy oxidation of molten lithium and molten sodium in the preparation process; the equipment is provided with a stirring device, protective gas, a die head block, cooling and extension structures in the die head, and can ensure uniform distribution of the molten metal and prevent the occurrence of bead condensation; the use of the protective gas can effectively isolate air and reduce oxidation of the metal; the die head block is helpful to control the flow direction of the molten metal and the thickness of the coating layer; the cooling and extension structures can ensure uniform shrinkage of the coating layer in the cooling process and avoid the generation of cracks.

[0094] In a second aspect, the utility model provides a kind of manufacturing equipment of composite strip, including the composite strip of first aspect described;

[0095] The manufacturing equipment includes:

[0096] Conveying system 2 for continuously conveying substrate 1;

[0097] Coating mechanism 3 includes die head 31, and the die head 31 is used to melt liquid coating to continuously conveyed substrate 1 under protective atmosphere;

[0098] Melt liquid transmission system 4 is used to melt liquid to die head 31 under protective atmosphere.

[0099] Through the cooperative work of above mechanism, the coating of substrate 1 is realized.

[0100] As some specific schemes, the die head 31 has upper die head 311, lower die head 312 two parts;Upper die head 311 and lower die head 312 cover and form a hollow liquid storage tank 313, for storing melt liquid;

[0101] The liquid storage tank 313 is internally provided with rotatable stirring device 314 for stirring melt liquid;

[0102] Stirring device 314 is also provided with detachable sealing device 315 at both ends;For sealing effect to liquid storage tank 313 under the cover condition of die head 31, prevent melt liquid in liquid storage tank 313 from leaking and oxidizing, affect the preparation of composite strip;

[0103] At least one of the sealing devices 315 is provided with a high-pressure protective gas inlet 3151 which is in communication with the liquid storage tank 313; the protective gas is introduced into the die head 31 to ensure that the molten liquid in the liquid storage tank 313 is always under a protective atmosphere during the feeding and discharging coating of the die head 31; the oxidation and pollution of the molten liquid are prevented, and the uniform and continuous coating of the molten liquid is realized to prepare the composite tape.

[0104] As some specific solutions, the stirring device 314 comprises a stirring rod 3141 and a stirring shaft 3142 for driving the stirring rod 3141 to rotate; the stirring rod 3141 is accommodated in the liquid storage tank 313 and is used for stirring the molten liquid to prevent the molten liquid from being precipitated, solidified or uneven during the coating process, so as to ensure the continuity and consistency of the coating layer 11.

[0105] As some specific solutions, the stirring rod 3141 and the stirring shaft 3142 are fixedly connected, and the rotation of the stirring device 314 is realized through an external transmission device 3143. The connection mode between the stirring rod 3141 and the stirring shaft 3142 or the connection mode of the external transmission device 3143 is not limited in principle, and a suitable connection mode can be selected by a person skilled in the art according to the needs; for example, the stirring rod 3141 and the stirring shaft 3142 can be threadedly connected, welded, keyed or connected in other mechanical connection modes; the transmission device 3143 for realizing the rotation of the stirring device 314 can be arranged inside or outside the stirring device 314 or at other positions as required.

[0106] The width and length of the stirring rod 3141 are not limited in principle, but it is better to basically cover the entire space of the liquid storage tank 313, while avoiding the direct contact between the stirring rod 3141 and the wall of the liquid storage tank 313, reducing the wear of the wall of the liquid storage tank 313 during the stirring process, and ensuring the overall stirring effect. A person skilled in the art can select a suitable length and width design according to the actual needs, for example, the width and length of the stirring rod 3141 can be designed to be 60%-95% of the diameter and length of the space of the liquid storage tank 313, respectively.

[0107] As some specific solutions, the shape of the stirring rod 3141 is not limited, and exemplary shapes can be selected from one or more of a rectangle, a square, a circle, and an oval.

[0108] As some specific solutions, the upper die head 311 and the lower die head 312 are respectively provided with ports 3131 capable of allowing the stirring device 314 to pass through at the end positions of the liquid storage tank 313, the inner walls of the ports 3131 are provided with inner wall grooves 31311, the stirring device 314 is provided with groove channels 31312 matched and embedded with the inner wall grooves 31311, so as to enable the stirring device 314 to be rotationally fixed on the ports 3131; specifically, the groove channels 31312 are arranged on the stirring shaft 3142 of the stirring device 314. The outer walls of the ports 3131 are provided with outer grooves 31313 for fixing the sealing device 315, so as to realize the sealing of the die head 31.

[0109] As some specific solutions, the sealing device 315 further comprises a sealing cover plate 3152 and a cover plate protruding portion 3153, the diameter of the sealing cover plate 3152 is greater than that of the cover plate protruding portion 3153, and the sealing cover plate 3152 is integrally arranged with the cover plate protruding portion 3153; the cover plate protruding portion 3153 is sealingly inserted into the outer groove 31313 of the outer wall of the port 3131; thereby realizing the mechanical sealing of the liquid storage tank 313, preventing the liquid storage tank 313 from leaking, solidifying and blocking, and preventing air from entering to cause the oxidation of the molten liquid, so as to facilitate the continuous and uniform coating of the die head 31 on the base material 1 to prepare the composite tape.

[0110] As some specific solutions, the sealing cover plate 3152 is provided with the high-pressure protective gas inlet 3151; meanwhile, the port 3131 is provided with an inlet channel 3154 corresponding to the high-pressure protective gas inlet 3151, the inlet channel 3154 is communicated with the inner wall groove 31311, and the inlet of the liquid storage tank 313 is realized.

[0111] As some specific solutions, the die head 31 further comprises a gasket 316, the gasket 316 is arranged in the area between the liquid storage tank 313 and the edge of the die head, the gasket 316 is provided with a gasket opening 3161 towards the edge of the die head, and the uniform distribution and discharge of the molten liquid are realized through the gasket opening 3161; on the die head 31, the edge of the die head corresponding to one side of the gasket opening 3161 is the die head discharge port 317.

[0112] As some specific solutions, the number, thickness and width of the gasket openings 3161 are consistent with those of the coating layers 11 of the composite tape; when the molten liquid is discharged through the gasket openings 3161 to coat the continuously conveyed base material 1, the preparation of the coating layers 11 with different numbers, thicknesses and widths on the base material 1 can be realized by adjusting the number, thickness and width of the gasket openings 3161; thereby obtaining the composite tape with multiple continuous and uniform coating layers 11.

[0113] As some specific solutions, the gasket 316 is provided with at least two positioning pins 3162, and the positioning pins 3162 are used to fix the gasket 316 on the die head 31.

[0114] The number, width and length of the gasket opening 3161 are not limited in principle, and a person skilled in the art can set them according to different coating layer 11 thicknesses, the number and width of the parallel distribution on the base material 1, so that continuous and uniform coating on the base material 1 is realized, and a composite tape with multiple coating layers 11 is prepared.

[0115] As some specific solutions, the shape of the gasket opening 3161 is not limited, and exemplary shapes can be selected from one or more of straight lines, waves, and arcs to adapt to different coating requirements and effects.

[0116] As some specific solutions, the die head 31 further comprises a fine adjustment mechanism 318; the fine adjustment mechanism 318 is arranged on the upper die head 311, and specifically above the die head discharge port 317. The size of the die head discharge port 317 is adjusted by the fine adjustment mechanism 318 to adapt to the coating requirements of base materials 1 and molten liquid of different thicknesses, and a uniform and continuous composite tape is prepared. The design of the fine adjustment mechanism 318 enables the operator to accurately control the thickness of the coating layer 11, thereby realizing accurate regulation of the thickness of the lithium layer of the composite tape. In addition, the addition of the fine adjustment mechanism 318 also improves the flexibility and applicability of the equipment, enabling it to adapt to different specifications of production requirements.

[0117] As some specific solutions, the fine adjustment mechanism 318 comprises an adjusting plate 3181 and at least two parallel arranged threaded rods 3182; the adjusting plate 3181 is provided with threaded holes 3183 corresponding to the threaded rods 3182, the threaded rods 3182 are connected with the adjusting plate 3181 through the threaded holes 3183, and the setting position of the adjusting plate 3181 can be relatively fixed with the position of the upper die head 311. The adjusting free end of the threaded rod 3182 acts on the upper die head 311, and is used to change the opening size of the die head discharge port 317 by applying a force to the upper die head 311 to adapt to the coating requirements of base materials 1 and molten liquid of different thicknesses.

[0118] Further, the adjusting plate 3181 can be relatively fixed with the position of the upper die head 311 through an external fixing device 319. The fixing device for fixing the adjusting plate 3181 is not limited in principle in the utility model; a person skilled in the art can select a suitable fixing device 319 according to the setting position.

[0119] As some specific solutions, the die head 31 further comprises a die head heating device 33; the die head heating device 33 is used to provide the temperature of the die head 31 to prevent the solidification of the molten liquid.

[0120] The specific position, mode and number of the die head heating device 33 are not limited, and a person skilled in the art can select and design according to actual needs; the setting position of the die head heating device 33 of the utility model is preferably accommodated in the hollow cavity opened in the die head 31; for example, one heating device can be respectively arranged in the upper die head 311 and the lower die head 312, so that the temperature of the die head 31 is uniform, the uniformity and quality of coating are further improved, and the molten liquid is prevented from solidifying. The heating devices of the upper die head 311 and the lower die head 312 can be independently controlled to adapt to the heating requirements of different molten liquids.

[0121] The die head 31 of the utility model further comprises a die head feeding port 331 and a die head backflow port 332; the molten liquid transmission system 4 is connected with the die head feeding port 331 and the die head backflow port 332, so that feeding of the die head 31 is realized when the die head 31 is coated, and when the die head 31 stops coating, the molten liquid in the die head 31 flows back to the molten liquid storage tank 43, so that circulation of the molten liquid in the transmission system is realized. The specific setting position of the die head feeding port 331 and the die head backflow port 332 is not limited in principle; a person skilled in the art can select and design according to actual needs; as some examples, the die head feeding port 331 can be arranged on one side of the upper die head 311, and the die head backflow port 332 can be arranged on one side of the lower die head 312.

[0122] As some specific schemes, the coating mechanism 3 further comprises a die head stop block 32; the die head stop block 32 is movably arranged on one side of the die head, and is used for covering the die head 31 when the die head 31 is not coated, so as to prevent the die head 31 from leaking liquid;

[0123] As some specific schemes, the die head stop block 32 comprises a movable support 321 and a baffle 322; the baffle 322 is detachably arranged on the support 321 and close to one side of the die head 31, and is used for covering the discharge side of the die head 31, so as to prevent liquid leakage, oxidation and solidification blockage.

[0124] In the utility model, the support 321 is movably arranged on the fixing device 319, and the movement of the support 321 is realized by adjusting the fixing device 319; the movement mode and position of the support 321 are not limited, and a person skilled in the art can select the position of the support 321 and the fixing device 319 according to actual needs.

[0125] As some specific schemes, the die head stop block 32 further comprises a stop block heating device 323; the stop block heating device 323 is detachably arranged on the support 321 and away from one side of the die head 31; the stop block heating device 323 is used for providing a heating temperature, maintaining the fluidity of the molten liquid, and preventing the molten liquid from solidifying.

[0126] As some specific solutions, the die block 32 is movably arranged at one side of the die discharge port 317 of the die 31.

[0127] As some specific solutions, a waste liquid collecting groove 324 is detachably arranged below the baffle 322 for collecting excess molten liquid.

[0128] As some specific solutions, the molten liquid transmission system 4 comprises a feeding and gas exchange measuring bin 41, a melting tank 42, a molten liquid storage tank 43, and a protective gas tank 44. One end of the protective gas tank 44 is independently connected with the feeding and gas exchange measuring bin 41, the melting tank 42, and the molten liquid storage tank 43 respectively, for realizing protection of the molten liquid and preventing the molten liquid from being oxidized. The other end is connected with the high-pressure protective gas inlet 3151 on the die 31, for realizing protection of the molten liquid in the die 31.

[0129] The feeding and gas exchange measuring bin 41 is used for adding materials under the protection of the protective gas.

[0130] The melting tank 42 is used for receiving materials from the feeding and gas exchange measuring bin for melting treatment under the action of the protective gas.

[0131] The molten liquid storage tank 313 is responsible for receiving the molten liquid from the melting tank 42 under the action of the protective gas and transmitting the molten liquid to the die 31, realizing continuous liquid feeding coating of the die 31, and preparing a composite tape with a uniform and continuous coating layer 11.

[0132] As some specific solutions, the molten liquid transmission system 4 is further provided with a solution pump 45, which realizes feeding of the die 31.

[0133] As some specific solutions, the molten liquid transmission system 4 further comprises a conveying pipe 46, which is used for sequentially connecting various parts of the molten liquid transmission system 4, realizing smooth transmission of the molten liquid.

[0134] As some specific solutions, the molten liquid transmission system 4 further comprises a vacuum pump 47, which is connected with the feeding and gas exchange measuring bin 41, for ensuring stability of the pressure in the feeding and gas exchange measuring bin 41 and preventing air from entering the system to cause oxidation of the molten liquid. The vacuum pump 47 and the conveying pipe 46 jointly realize overall coverage of the protective gas of the molten liquid transmission system 4.

[0135] The molten liquid conveying system 4 and the die 31 are fully covered by the protective gas, which is beneficial to effectively prevent the molten liquid from being oxidized by contacting with air during the conveying process, thereby prolonging the service life of the molten liquid and improving the quality of the composite strip. On the other hand, the protective gas covers the inside of the die 31, which is beneficial to solve the problems of oxidation, corrosion and high-precision coating of the molten liquid metal; at the same time, the input of the protective gas into the inside of the die 31 also plays a role of protective gas sealing, effectively ensuring that the inside of the entire molten liquid conveying mechanism is in a protective gas environment; and is beneficial to ensuring the good adhesion of the coating layer 11 to the substrate 1 when the substrate 1 is coated. In addition, the use of the protective gas can also reduce the volatilization loss of the molten liquid during the coating process, thereby further improving the material utilization rate.

[0136] As some specific solutions, the manufacturing equipment can further have a substrate heating mechanism 8; the substrate heating mechanism 8 is used for heating the substrate 1 before coating; and is beneficial to improving the wettability of the molten lithium and enhancing the combination of the molten lithium and the substrate 1.

[0137] Further, the substrate heating mechanism 8 comprises two parts of an upper assembly 81 and a lower assembly 82; the upper assembly 81 and the lower assembly 82 are combined to form a hollow chamber; a plurality of groups of passing rollers 83 are arranged in the chamber; and the passing rollers 83 are used for conveying the substrate 1 and ensuring that the substrate 1 can be uniformly heated during the heating process.

[0138] Further, the upper assembly 81 and the lower assembly 82 are combined to form a hollow chamber; a plurality of groups of passing rollers 83 are arranged in the chamber; and the passing rollers 83 are used for conveying the substrate 1 and ensuring that the substrate 1 can be uniformly heated during the heating process.

[0139] Further, the upper assembly 81 and the lower assembly 82 are combined to form a hollow chamber; a plurality of groups of passing rollers 83 are arranged in the chamber; and the passing rollers 83 are used for conveying the substrate 1 and ensuring that the substrate 1 can be uniformly heated during the heating process.

[0140] The specific setting positions of the hot gas inlet 86 and the hot gas outlet 87 are not limited in principle in the utility model; the skilled person in the art can select and design according to actual needs; as some examples, the hot gas inlet 86 can be arranged on the outer side of the lower assembly 82, and the hot gas outlet 87 can be arranged on the outer side of the upper assembly 81.

[0141] Further, the substrate heating mechanism 8 is further connected with a heating box 88; the heating box 88 is connected with the hot gas inlet 86 of the substrate heating mechanism 8 through a pipeline. The heating of the gas is realized through the heating box 88, and then the heating of the substrate 1 is realized by entering the inside of the substrate heating mechanism 8.

[0142] The specific position of the heating box is not limited in the utility model, and the skilled person in the art can select and design according to actual needs; as some examples, the utility model connects the heating box 88 outside the substrate heating mechanism 8 to realize the heating of the substrate 1.

[0143] The utility model discloses a lithium coating layer is further optimized equipment process to lithium as the main part, before the base material is coated lithium melt liquid, further heating treatment is carried out to the base material, when the lithium melt liquid is coated on the heated base material, the contact angle of lithium melt liquid can be reduced, thereby the combination of coating layer and base material is strengthened, and then through the subsequent cooling and setting and extension processing, the coating layer realizes the relatively thin thickness, and the coating layer is more uniform and flat, and it is helpful to eliminate the scratch, and better preparation effect is obtained.

[0144] As a further scheme, the manufacturing equipment of the composite tape further includes a cooling and setting mechanism 5 and a calendering mechanism 6, the cooling and setting mechanism 5 is used to cool and set the coated base material 1, the calendering mechanism 6 is used to calender the cooled and set base material 1, and the conveying system 2 includes an unwinding system 21 and a winding system 22. Through the cooperation of the unwinding system 21 and the winding system 22, the continuous conveying of the base material 1 is realized.

[0145] Further, the unwinding system 21 includes an unwinding shaft 211 and at least one group of unwinding rolling rollers 212, the unwinding shaft 211 is used to sleeve the base material 1, the unwinding rolling rollers 212 are arranged between the unwinding shaft 211 and the coating mechanism 3, and are used to realize the continuous supply of the base material 1, while keeping the tension of the base material 1 average, ensuring that the base material 1 runs stably in the coating process, avoiding the relaxation or fracture phenomenon, thereby ensuring the flatness and quality of the coating layer 11.

[0146] Further, the winding system 22 is arranged behind the calendering mechanism 6 along the conveying direction of the base material 1, and is used to wind the prepared composite tape, the winding system 22 includes a winding shaft 221 and at least one group of winding rolling rollers 222, the winding shaft 221 is used to realize the winding of the base material 1, and the winding rolling rollers 222 are arranged between the winding shaft 221 and the calendering mechanism 6, and are used to keep the tension of the composite tape uniform in the winding process, ensuring that the wound composite tape is flat and wrinkle-free.

[0147] As some specific schemes, the cooling and setting mechanism 5 is arranged behind the coating mechanism 3 along the conveying direction of the base material 1, and is used to cool and set the coated composite tape. The cooling and setting mechanism 5 includes at least one group of upper cooling rollers 51 and lower cooling rollers 52 arranged on the upper and lower sides of the base material 1 and coaxially arranged, and is used to cool and set the coated base material 1 quickly, ensuring that the shape and size of the coating layer are stable.

[0148] As some specific solutions, the calendering mechanism 6 is arranged behind the cooling and shaping mechanism 5 along the conveying direction of the base material 1, and is used for further calendering treatment of the base material 1 after cooling and shaping to improve the flatness and adhesion of the coating. The calendering mechanism 6 comprises at least one set of coaxially arranged calendering rollers 61 arranged on the upper and lower sides of the base material 1, and the calendering rollers 61 can be independently adjusted to adapt to composite tapes of different thicknesses and materials. By accurately controlling the pressure and speed of the calendering rollers 61, the scratches on the surface of the base material 1 after coating can be further eliminated, and a composite tape with a plurality of continuous and uniform coating layers 11 can be prepared.

[0149] As some specific solutions, the composite tape manufacturing equipment further comprises an encoding mechanism 7 arranged between the calendering mechanism 6 and the winding system 22, and used for encoding the composite tape. The encoding mechanism 7 comprises at least one set of coaxially arranged tension rollers 71 arranged on the two sides of the base material 1, and is used for further ensuring the flatness of the base material 1 and the stability and accuracy in the encoding process. The encoding mechanism 7 further comprises an encoding rolling roller 72 and an encoder 73, and is used for realizing the continuous rolling and encoding of the base material 1.

[0150] In a third aspect, the utility model provides a kind of preparation method of composite tape;Including the composite tape described in first aspect and the composite tape manufacturing equipment described in second aspect;Its steps include:

[0151] S1: the raw material of metal coating layer is added to the charging and gas exchange measuring bin 41 under the protection atmosphere, and the charging and gas exchange measuring bin 41 is treated by vacuum air exchange by vacuum pump 47, to ensure that the raw material is charged in the oxygen-free environment;

[0152] S2: material is entered into melting tank 42 by conveying pipe 46 from charging and gas exchange measuring bin 41, and the molten liquid after melting under the protection atmosphere is sequentially conveyed to die head 31 by conveying pipe 46 through molten liquid storage tank 43 and solution pump 45;

[0153] S3: under the protection atmosphere, the molten liquid is heated and stirred by heating device and stirring device 314 in die head 31;

[0154] S4: the base material 1 is supplied by unwinding system 21, and the base material 1 reaches the side of die head discharge port 317 of die head baffle 32 under the die head discharge port 317; The molten liquid after melting is coated on the base material 1; When coating is stopped, die head baffle 32 is placed on one side of die head discharge port 317.

[0155] S5: the coated base material 1 is rapidly cooled and shaped by cooling and shaping mechanism 5;The base material 1 after cooling and shaping is further calendered by calendering mechanism 6;The base material 1 is encoded by encoding device;The calendered base material 1 is wound by winding system 22;Finally, the composite tape with coating layer 11 is obtained.

[0156] In the preparation method of the utility model, adopt a continuous production flow, this flow can realize to the continuous coating of base material, ensured the uniformity and quality stability of coating layer. Meanwhile, through to the base material continuous coating, die head heating temperature, cooling temperature, calendering temperature and the setting of roll gap spacing, ensure that the base material can obtain consistent physical properties and mechanical properties after uniform coating. Through the optimized process parameters, can effectively reduce the waste rate in production process, improve production efficiency, reduce production cost. In addition, in the preparation method of the utility model, the whole production process is carried out in the protective atmosphere, effectively prevent the oxidation produced by the contact of molten liquid and air, ensure the quality of preparation composite tape.

[0157] As some specific schemes, the base material 1 in S4 can also pass through the base material heating mechanism 8 before reaching the die head discharge port 317, and the base material passes through the unwinding mechanism 21, the base material heating mechanism 8 and the die head discharge port 317 in sequence for coating.

[0158] Further, the temperature range of the base material heating mechanism 8 is 100-350 degrees.

[0159] As some specific schemes, the die head 31 in S2 is covered by the movable die head block 32 when not coating, preventing liquid leakage, solidification blockage and molten liquid oxidation pollution.

[0160] Further, the heating temperature of the die head block 32 is selected from 50-500 degrees.

[0161] The die head block temperature in this temperature range is beneficial to prevent liquid leakage and solidification when covering the die head, prevent die blockage or the generation of solidified particles caused by too low temperature, and affect the uniformity of composite tape preparation.

[0162] As some specific schemes, the temperature range of the die head 31 is selected from 100-500 degrees when coating. Selecting appropriate die head temperature is beneficial to realize uniform coating of molten liquid, ensure the uniformity of coating thickness on the surface of the base material, and thus obtain good physical and mechanical properties. In addition, appropriate die head temperature helps molten liquid have good fluidity and spreadability during coating, further improving the preparation quality of composite tape.

[0163] As some specific schemes, when the substrate 1 is cooled and shaped in S3, there is at least one group of upper cooling rollers 51 and lower cooling rollers 52 on the upper and lower sides of the substrate 1 respectively; wherein, the temperature of the upper cooling roller 51 is selected from 15-150°C; the temperature of the lower cooling roller 52 is selected from 15-100°C; the relationship between the roller gap distance d between each group of upper cooling rollers 51 and lower cooling rollers 52 and the total thickness D of the substrate 11 after the die head 31 is completed is d=mD, and m is selected from 0.7-1.6.

[0164] Furthermore, the temperature of the upper cooling roller 51 is preferably selected from 20-50°C; the temperature of the lower cooling roller 52 is selected from 20-30°C.

[0165] The appropriate chill roll temperature and gap distance facilitate rapid cooling and shaping of the melt on the substrate after coating, reducing energy consumption during production. Furthermore, the high surface tension of the melt, which tends to form beads, helps prevent uneven coating. Precisely controlling the chill roll temperature and gap distance effectively prevents substrate deformation or excessive internal stress in the coating caused by excessively fast or slow cooling. Furthermore, appropriate temperature and gap settings ensure that the composite tape maintains appropriate tension during the cooling process, improving product flatness and dimensional stability.

[0166] As some specific schemes, the calendering treatment in S4 is achieved by at least one group of stretching rollers 61 coaxially arranged on the upper and lower sides of the substrate 1, and the relationship between the roller gap distance y between each group of stretching rollers 61 and the total thickness Y of the substrate 1 after cooling and shaping is y=nY, where n is selected from 0.5-1.3.

[0167] The temperature range of the pressing roller is selected from 80-200°C.

[0168] Selecting the appropriate range of calendering roller temperature and roller gap distance can effectively eliminate stress concentration during the cooling and shaping process, avoid cracks or fractures inside the material; at the same time, further eliminate scratches on the surface of the composite strip and ensure a uniform and consistent coating layer.

[0169] As some specific solutions, there is also a coding operation between S4 and S5 for coding the substrate 1.

[0170] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, and are not all embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0171] Example 1

[0172] Copper foil (thickness: 6 μm) was selected as the substrate 1, and lithium metal was used as the molten liquid; 2.0 kg of lithium metal was added to the feeding and air metering bin 41, and vacuum air metering treatment was performed by the vacuum pump 47; the lithium metal sequentially passed through the delivery pipe 46 into the melting tank 42 (temperature: 280 degrees) and the molten liquid storage tank 43 (temperature: 280 degrees); and then was delivered to the die head 31 by the solution pump 45.

[0173] The molten liquid was heated (temperature: 280 degrees) and stirred (rotation speed: 5 r / min) by the heating device and stirring device 314 in the die head 31 under the protection of the protective gas; the die head block 32 (temperature: 200 degrees) was used to cover the die head discharge port 317; the copper foil was continuously supplied by the unwinding system 21, and when the copper foil reached below the die head discharge port 317, the die head baffle 322 was moved to remove the die head baffle 322, and the molten lithium metal was coated on the copper foil.

[0174] After the coating was completed, when the coated substrate 1 entered the cooling and shaping mechanism 5, rapid cooling and shaping treatment was performed by the cooling and shaping mechanism 5 (the temperature of the cooling roller 51 above the substrate 1: 50 degrees; the temperature of the cooling roller 51 below the substrate 1: 30 degrees; the roller gap of each set of cooling rollers 51: 9 μm).

[0175] Subsequently, the cooled and shaped substrate 1 was subjected to calendering treatment by the calendering mechanism 6 (the temperature of the calendering rollers 61 above and below the substrate 1: 130 degrees; the roller gap of each set of calendering rollers 61: 7.5 μm; the pressure of each set of calendering rollers 61: 0.5 tons).

[0176] Then, the calendered substrate 1 was subjected to coding treatment by the coding mechanism 7.

[0177] Finally, the composite tape was wound by the winding system 22, and the preparation of the composite tape with a lithium layer was completed.

[0178] Example 2

[0179] The specific operation method and conditions were the same as in Example 1, except that the heating temperature of the die head 31 was 320 degrees.

[0180] Example 3

[0181] The specific operation method and conditions were the same as in Example 1, except that during the cooling and shaping treatment, the temperature of the upper cooling roller 51 was selected to be 55 degrees, and the temperature of the lower cooling roller 52 was selected to be 35 degrees.

[0182] Example 4

[0183] The specific operation method and conditions were the same as in Example 1, except that during the cooling and shaping treatment, the shaping roller gap between each set of cooling rollers was 10 μm.

[0184] Example 5

[0185] The specific operation method and conditions are the same as in Example 1; the difference is that during the calendering process, the temperature of the upper and lower spreader rollers 61 in each group is selected from 150 degrees.

[0186] Example 6

[0187] The specific operation method and conditions are the same as in Example 1; the difference is that during the calendering process, the temperature of the upper and lower spreader rollers 61 in each group is selected from 115 degrees.

[0188] Example 7

[0189] The specific operation method and conditions are the same as in Example 1; the difference is that during the calendering process, the spreader roller 61 gap between each group of spreader rollers 61 is 8 μm.

[0190] Example 8

[0191] The specific operation method and conditions are the same as in Example 1; the difference is that during the calendering process, the spreader roller 61 pressure of each group of spreader rollers 61 is 0.2 tons.

[0192] Example 9

[0193] The specific operation method and conditions are the same as in Example 1; the difference is that the composition of the molten liquid is selected from Li: graphene = 1:0.05.

[0194] Example 10

[0195] The specific operation method and conditions are the same as in Example 1; the difference is that the substrate 1 is selected from a sodium battery negative electrode sheet (main material is hard carbon) (thickness: 150 μm); sodium metal is used as the molten liquid; during the cooling and shaping process, the temperature of the upper cooling roller 51 is selected from 50 degrees; the temperature of the lower cooling roller 52 is selected from 30 degrees. The shaping roller gap between each group of cooling rollers is 153 μm.

[0196] During the calendering process, the temperature of the upper and lower spreader rollers 61 in each group is selected from 80 degrees. The spreader roller 61 gap between each group of spreader rollers 61 is 146 μm. The spreader roller 61 pressure is 0.5 tons.

[0197] Example 11

[0198] The specific operation method and condition are the same as example 1; the difference is that the substrate heating mechanism 8 is added before the substrate 1 is coated; the substrate passes through the unwinding system 21, the substrate heating mechanism 8, the coating mechanism 3, the cooling and shaping mechanism 5, the calendering mechanism 6, the coding mechanism 7, and the winding system 22 in turn to complete the preparation of the composite tape; the specific steps of the substrate passing through the substrate heating mechanism 8 are as follows: the substrate 1 enters the inside of the substrate heating mechanism 8 through the substrate inlet 84, and then is output through the substrate outlet 85 under the conveying of the over roller 83; the substrate is conveyed by the over roller 83 and heated under the action of the protective gas with a temperature of 220±10 degrees.

[0199] Comparative example 1

[0200] The specific operation method and condition are the same as example 1; the difference is that the molten liquid is not stirred when the die head 31 coats the continuously supplied substrate 1.

[0201] Comparative example 2

[0202] The specific operation method and condition are the same as example 1; the difference is that the heating temperature of the die head 31 is 40 degrees.

[0203] Comparative example 3

[0204] The specific operation method and condition are the same as example 1; the difference is that the die head blocking piece 32 is not placed to cover the die head discharge port 317 when the die head 31 does not coat the liquid.

[0205] Comparative example 4

[0206] The specific operation method and condition are the same as example 1; the difference is that the temperature of the upper cooling roller 51 and the lower cooling roller 52 is 10 degrees when the cooling and shaping treatment is performed.

[0207] Comparative example 5

[0208] The specific operation method and condition are the same as example 1; the difference is that the temperature of the upper and lower calendering rollers 61 in each group is 50 degrees when the calendering treatment is performed.

[0209] Comparative example 6

[0210] The specific operation method and condition are the same as example 1; the difference is that the calendering roller 61 gap between each group of calendering rollers 61 is 4.5 μm when the calendering treatment is performed.

[0211] Comparative example 7

[0212] The specific operation method and condition are same as example 1; the difference is that: the manufacturing equipment and preparation steps of the utility model are not used; the lithium ion battery negative pole piece is calendered and compounded by using lithium foil by using the conventional method of prior art; the specific steps are: 5 mu m thick 150 mu m wide lithium foil is placed on 122 mu m thick 151 mu m wide negative pole piece, and then calendered and compounded by calendering machine.In the calendering process, the temperature of the upper and lower pressure expansion rollers 61 is set to room temperature, the roll gap of the pressure expansion rollers 61 is 110 mu m, and the pressure of the pressure expansion rollers 61 is 0.5 tons.

[0213] Specific test and method: the width is calculated by the difference of laser reflection spectrum of different materials by using laser measuring instrument, the width value of coating material is calculated, the width change range is automatically generated by referring to the set width center value; the thickness is calculated by the change of ray penetration intensity by using ray thickness gauge.

[0214] Table 1

[0215]

[0216]

[0217] Table 2

[0218]

[0219]

[0220] From the data of table 1 and table 2, it can be seen that the coating width, thickness and size after shaping of example 1 to example 10 are in the specified range, which shows that the manufacturing equipment and preparation steps of the utility model can obtain stable and uniform coating effect. The composite tape with continuous and uniform coating layer 11 is obtained; the problems of uneven coating layer 11 and inconsistent thickness in the prelithiation of pole piece in prior art are effectively solved.In addition, from table 2, it can be seen that the coulomb efficiency of the composite substrate 1 in the example is generally high, and the cycle performance is good, which shows that the manufacturing method and manufacturing equipment of the utility model have obvious advantages in improving the quality of composite tape, battery performance and production efficiency, and have high industrial application value.

[0221] In contrast, the comparative example 1 and the comparative example 2 cause the instability of the coating width and the thickness, and the serious scratch and the copper foil broken tape problem of the composite tape when the unreasonable die is used, which seriously affects the performance and the production efficiency of the battery. The comparative example 1 causes the uneven coating thickness and the solidified particles due to the fact that the molten liquid is not subjected to the stirring treatment, and finally the composite tape with the serious scratch is prepared. This is because the molten liquid is easy to form the solidified particles on the surface of the copper foil in the case of not being stirred, and the particles scratch the surface of the copper foil in the calendering process, so that the scratch appears on the surface of the composite tape, and the performance and the safety of the battery are affected.

[0222] In the comparative example 2, it can be seen that the copper foil is broken due to the solidified particles during the coating of the composite tape. This is because the heating temperature of the die 31 is too low, the molten liquid is not completely solidified during the coating, the solidified particles are attached to the surface of the copper foil, the coating layer 11 is uneven, and the copper foil is easy to be broken in the calendering process, so that the performance of the battery is affected.

[0223] It can be seen from the comparative example 3 that, compared with the manufacturing equipment of the embodiment, the die and the die block combination are used as the coating mechanism in the utility model, which can more favorably realize the uniform coating of the molten liquid and avoid the generation of the solidified particles. When the die 31 does not perform the liquid coating operation, the die block 32 is not subjected to the covering treatment in the comparative example 3, so that the solidified particles appear in the preparation process of the composite tape, the copper foil is broken, and the uniform and continuous composite tape cannot be successfully prepared for use. This is because the molten liquid is easy to be solidified and to block the die discharge port 317 in the case of not using the die block 32 for the covering treatment, air is easy to enter, the molten liquid is oxidized and contaminated, and the solidified particles are formed on the surface of the copper foil substrate 1 during the subsequent coating operation. The particles scratch the surface of the copper foil in the calendering process, so that the composite tape is broken, and the performance and the safety of the battery are affected. Therefore, the covering treatment of the die block 32 is more favorable to ensure the integrity of the composite tape.

[0224] It can also be seen from the embodiment 1-10 and the comparative examples 4, 5 and 6 that the optimized preparation method of the utility model is crucial for successfully preparing the continuous and uniform composite tape.

[0225] The temperature of the comparative example 4 is too low during the preparation of the composite tape, the molten liquid splashes everywhere, and the safe operation cannot be performed. Therefore, the production of the composite tape cannot be successfully prepared. This is because the temperature is too low, so that the molten liquid cannot be uniformly solidified on the surface of the copper foil, the molten liquid splashes everywhere, the safe operation cannot be performed, and the uniform coating effect cannot be obtained.

[0226] The comparative example 5 has a lower temperature of the compression roller 61 during the preparation of the composite tape, so that obvious scratches can be observed on the composite tape. This is due to the improper temperature setting of the compression roller 61, which causes uneven solidification of the molten liquid on the surface of the copper foil, and thus produces scratches. This uneven solidification process not only affects the surface quality of the composite tape, but also reduces the performance of the battery. Therefore, selecting the appropriate temperature of the compression roller 61 is crucial to ensure the uniformity of the coating layer 11 and the performance of the battery.

[0227] In the comparative example 6, the roll gap is set too small during the calendering process, which causes the copper foil to break during the calendering process. This indicates that the size of the roll gap needs to be accurately controlled during the coating process to avoid unnecessary damage to the copper foil. Proper roll gap setting can ensure the uniformity of the coating layer 11, while avoiding copper foil breakage and ensuring the smooth progress of the production process.

[0228] In the comparative example 7, the composite tape is prepared by directly calendering the lithium foil on the substrate 1 using the conventional method of the prior art. It can be observed that the surface of the composite tape has no obvious scratches, and the coulomb efficiency is high, but the cycle performance is poor. This is because the thickness of the lithium foil is limited, and the thinnest lithium foil available on the market is 5±1um. The negative electrode sheet in examples 1-9 and comparative examples 1-6 is graphite, and the pre-lithium amount required by the graphite negative electrode is 8-10%, which corresponds to a lithium layer thickness of 3±1um. The excess lithium supplement in comparative example 6 causes the capacity of the battery to rapidly decay during cycling.

[0229] As can be seen from example 10, the manufacturing equipment of the present application is also suitable for supplementing sodium for sodium-ion battery negative electrode sheets; it is illustrated that the equipment of the present application can not only successfully realize pre-lithiation to prepare a composite tape, but also be suitable for the preparation of other metal composite tapes; it has high flexibility and applicability; and has high industrial practical value.

[0230] As can be seen from examples 1-10 and example 11, further heating the substrate by the substrate heating mechanism 8 before coating is more conducive to reducing the contact angle of the lithium melt, which is conducive to further preparing a thinner coating layer, enhancing the bonding of the molten lithium and the substrate, and further improving the coulomb efficiency and cycle performance of the battery.

[0231] Figure 14 The contact angle between the metal lithium solution and the substrate during the coating of the substrate in example 1 is measured to be in the range of 30-60°; Figure 15For the metal lithium solution in the embodiment 11 when coating the substrate after heating, the contact angle between the lithium molten liquid and the heated substrate is measured to be in the range of 1-10°; it is explained that the further optimization of the utility model, heating the substrate before coating can further reduce the contact angle of the metal molten liquid, thereby being more beneficial to the preparation of a thinner coating; and the improvement of the battery performance is most fully exerted.

[0232] It should be noted that the above is only one of the embodiments of the utility model, and does not limit the utility model, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. An apparatus for manufacturing a composite tape, characterized by comprising: The manufacturing equipment of the composite tape comprises: a conveying system (2) for continuously conveying a substrate (1); a coating mechanism (3) comprising a die head (31) for melt liquid coating of the continuously conveyed substrate (1) under a protective atmosphere; a melt liquid conveying system (4) for conveying melt liquid to the die head (31) under a protective atmosphere.

2. The manufacturing apparatus of the composite tape according to claim 1, characterized by, The die head (31) has two parts of an upper die head (311) and a lower die head (312); the upper die head (311) and the lower die head (312) are combined to form a hollow liquid storage tank (313); The liquid storage tank (313) has a rotatable stirring device (314) inside; Both ends of the stirring device (314) are further provided with detachable sealing devices (315); at least one of the sealing devices (315) is provided with a high-pressure protective gas inlet (3151) in communication with the liquid storage tank (313).

3. The manufacturing apparatus of the composite tape according to claim 2, characterized by Among the upper die head (311) and the lower die head (312), a port (3131) capable of allowing the stirring device (314) to pass through is arranged at the end position of the liquid storage tank (313); an inner wall groove (31311) is arranged on the inner wall of the port (3131); a groove (31312) matching the inner wall groove (31311) is arranged on the stirring device (314) for fixing the stirring device (314); an outer groove (31313) is arranged on the outer wall of the port (3131) for fixing the sealing device (315); Further, the sealing device (315) further comprises a sealing cover plate (3152) and a cover plate protruding portion (3153); the diameter of the sealing cover plate (3152) is greater than that of the cover plate protruding portion (3153), and the sealing cover plate (3152) and the cover plate protruding portion (3153) are integrally arranged; the cover plate protruding portion (3153) is sealingly inserted into the outer groove (31313) of the outer wall of the port (3131); Further, the sealing cover plate (3152) is provided with the high-pressure protective gas inlet (3151); meanwhile, the port (3131) is provided with an air inlet channel (3154) corresponding to the high-pressure protective gas inlet (3151), the air inlet channel (3154) is in communication with the inner wall groove (31311), and the air inlet of the liquid storage tank (313) is realized.

4. The manufacturing apparatus of the composite tape according to claim 2, characterized by The die head (31) further comprises a gasket (316) arranged in the area between the liquid storage tank (313) and the edge of the die head; the gasket (316) is provided with a gasket opening (3161) towards the edge of the die head, and the gasket opening (3161) realizes uniform distribution and discharge of the melt liquid; wherein, on the die head (31), the edge of the die head corresponding to one side of the gasket opening (3161) is the die head discharge port (317); The die head (31) further comprises a fine adjustment mechanism (318); the fine adjustment mechanism (318) is arranged on the upper die head (311); The die head (31) further has a die head heating device (33). Further, the gasket (316) is provided with at least two positioning pins (3162), and the gasket (316) is fixed on the die head (31) through the positioning pins (3162); Further, the fine adjustment mechanism (318) comprises an adjusting plate (3181) and at least two parallel arranged threaded rods (3182); the adjusting plate (3181) is provided with threaded holes (3183) corresponding to the threaded rods (3182), the threaded rods (3182) are connected with the adjusting plate (3181) through the threaded holes (3183), the setting position of the adjusting plate (3181) can be fixed relative to the position of the upper die head (311), and the free end of the threaded rod (3182) acts on the upper die head (311) to change the opening size of the die head discharge port (317) by applying force to the upper die head (311).

5. The manufacturing apparatus of the composite tape according to claim 1, wherein The manufacturing equipment can also have a substrate heating mechanism (8); and be used for heating the substrate (1) before coating; Further, the substrate heating mechanism (8) comprises two parts of an upper assembly (81) and a lower assembly (82); the upper assembly (81) and the lower assembly (82) are combined to form a hollow chamber; a plurality of groups of rollers (83) are arranged in the chamber; Further, the upper assembly (81) and the lower assembly (82) are provided with a substrate inlet (84) and a substrate outlet (85) along the conveying direction of the substrate (1) at the combined contact part; Further, the upper assembly (81) and the lower assembly (82) are respectively and independently provided with a hot gas inlet (86) and a hot gas outlet (87) at the two sides outside the combination; Further, the substrate heating mechanism (8) is also connected with a heating box (88); and the heating box (88) is connected with the hot gas inlet (86) of the substrate heating mechanism (8) through a pipeline.

6. The manufacturing apparatus of the composite tape according to claim 1, wherein The coating mechanism (3) further comprises a die head stopper (32); the die head stopper (32) is movably arranged on one side of the die head (31); and is used for covering the die head (31) when the die head (31) is not coating, to prevent liquid leakage of the die head (31); Further, the die head stopper (32) comprises a movable support (321) and a baffle (322); the baffle (322) is detachably arranged on the support (321) and close to one side of the die head (31); Further, the die head stopper (32) further comprises a stopper heating device (323), which is detachably arranged on the support (321) and away from one side of the die head (31); Further, a waste liquid collecting groove (324) is detachably arranged below the baffle (322).

7. The manufacturing apparatus of the composite tape according to claim 1, wherein The molten liquid transmission system (4) comprises a feeding and air exchange metering bin (41), a melting tank (42), a molten liquid storage tank (43) and a protective gas tank (44); Further, one end of the protective gas tank (44) is independently connected with the feeding and air exchange metering bin (41), the melting tank (42) and the molten liquid storage tank (43) respectively; and the other end is connected with a high-pressure protective gas inlet (3151) on the die head (31). Further, the molten liquid conveying system (4) is further provided with a solution pump (45), through which the feeding of the die head (31) is realized. Further, the molten liquid conveying system (4) further comprises a conveying pipe (46) for sequentially connecting various parts of the molten liquid conveying system (4). Further, the molten liquid conveying system (4) further comprises a vacuum pump (47) connected with the feeding and air exchange metering bin (41).

8. The manufacturing apparatus of the composite tape according to claim 1, characterized by The manufacturing equipment of the composite tape further comprises a cooling and shaping mechanism (5) and a calendering mechanism (6); the cooling and shaping mechanism (5) is used for cooling and shaping the coated substrate (1); and the calendering mechanism (6) is used for calendering the cooled and shaped substrate (1). The conveying system (2) comprises an unwinding system (21) and a winding system (22). Further, the unwinding system (21) comprises an unwinding shaft (211) and at least one set of unwinding rolling rollers (212); the unwinding shaft (211) is used for sleeving the substrate (1), and the unwinding rolling rollers (212) are arranged between the unwinding shaft (211) and the coating mechanism (3) and are used for realizing the continuous feeding of the substrate (1). Further, the winding system (22) is arranged behind the calendering mechanism (6) along the conveying direction of the substrate (1) and comprises a winding shaft (221) and at least one set of winding rolling rollers (222); the winding rolling rollers (222) are arranged between the winding shaft (221) and the calendering mechanism (6).

9. The manufacturing apparatus of the composite tape according to claim 8, wherein The cooling and shaping mechanism (5) is arranged behind the coating mechanism (3) along the conveying direction of the substrate (1) and is used for cooling and shaping the coated composite tape; the cooling and shaping mechanism (5) comprises at least one set of upper cooling rollers (51) and lower cooling rollers (52) arranged on the upper side and the lower side of the substrate (1) coaxially. Further, the calendering mechanism (6) is arranged behind the cooling and shaping mechanism (5) along the conveying direction of the substrate (1), and the calendering mechanism (6) comprises at least one set of calendering rollers (61) arranged on the upper side and the lower side of the substrate (1) coaxially.

10. The manufacturing apparatus of the composite tape according to claim 1, wherein The manufacturing equipment of the composite tape further comprises an encoding mechanism (7) arranged between the calendering mechanism (6) and the winding system (22); the encoding mechanism (7) comprises at least one set of tension rollers (71) arranged on the upper side and the lower side of the substrate (1) coaxially, and further comprises an encoding rolling roller (72) and an encoder (73).

Images