Lithium supplementing device for pole piece

Abstract

The utility model provides a pole piece lithium supplementing device and relates to the field of power batteries. The pole piece lithium supplementing device comprises an unwinding shaft; a winding shaft; the melting device comprises a melting crucible used for bearing molten metal and a heating element arranged on the peripheral side of the melting crucible; the coating device comprises a slit extrusion coating head, the slit extrusion coating head is connected and communicated with the smelting crucible, and the end part of the coating head is positioned right above the pole piece; the gas nozzle is located on the side, facing the advancing direction of the pole piece, of the slit extrusion coating head, and the nozzle points to a liquid falling area of the slit extrusion coating head and is obliquely arranged; one end of the pressure gas pipe is connected with an external inert gas source, and the other end of the pressure gas pipe is connected with the smelting crucible. According to the technical scheme, the problems that in the prior art, the lithium supplementing width and uniformity of the pole piece are poor, the ultra-thin thickness cannot be met due to the fact that the lithium supplementing thickness precision is low are solved, meanwhile, the problem that an existing pole piece technology needs an auxiliary base material is solved, and the lithium supplementing cost is reduced.

Description

Technical Field

[0001] The invention generally relates to the field of power batteries, and in particular to a pole piece lithium replenishing device. Background Art

[0002] With the continuous improvement of the energy density of power batteries, the gram capacity and compaction density of existing negative electrode materials have reached their limits. At the same time, the initial charge and discharge efficiency of lithium-ion batteries with silicon-carbon materials as negative electrodes is low. The lithium loss during the charge and discharge process is one of the important reasons affecting the battery energy and battery cycle performance. In the existing technology, this part of the loss is generally compensated by lithium supplementation. The lithium supplementation technology can not only compensate for the initial loss of the anode, but also provide additional lithium sources, thereby greatly improving the energy density and cycle performance of lithium-ion batteries.

[0003] Before the improvement, the method for preparing ultra-thin lithium metal was mechanical rolling, which used mechanical pressure to roll thick lithium blocks into thin lithium foil. However, due to the high viscosity and poor mechanical adjustment ability of lithium metal itself, the ultra-thin lithium foil prepared by mechanical rolling can generally only be 20μm, and the thickness and accuracy of lithium supplementation are difficult to control. Utility Model Content

[0004] In view of the problems existing in the above-mentioned prior art, the utility model provides a lithium replenishing device for an electrode, comprising: a reel; a reel; a melting device, comprising a melting crucible for carrying molten metal, and a heating element arranged on the periphery of the melting crucible; a coating device, comprising a slit extrusion coating head, which is interconnected and communicated with the melting crucible, and the end of the coating head is located directly above the electrode; a gas nozzle, which is located on the side of the slit extrusion coating head facing the forward direction of the electrode, and the nozzle is inclined to point to the liquid falling area of ​​the slit extrusion coating head; a pressure gas pipe, one end of which is connected to an external inert gas source, and the other end is connected to the melting crucible. By having the above-mentioned technical features, the melting crucible can be convenient for adding different alloy elements, thereby improving the performance of lithium-ion batteries; and through the cooperation of the slit extrusion coating head and the gas nozzle, the molten metal is evenly blown to the surface of the electrode, and the thickness of the metal layer can be adjusted by adjusting the pressure of the gas nozzle and the extrusion amount of the slit extrusion coating head. The discharge width can be adjusted by replacing the gasket in the slit extrusion coating head to achieve coated lithium layers of different widths to meet the lithium replenishment needs of electrodes of different widths; the problems of electrode lithium replenishment width and uniformity in the prior art are solved, and the problem of low precision of lithium replenishment thickness and inability to meet ultra-thin thickness is solved. At the same time, the problem of the existing lithium replenishment process requiring an auxiliary substrate is also solved, thereby reducing the cost of lithium replenishment.

[0005] In some embodiments, a preheating device is further provided between the unwinding shaft and the coating device, and the preheating device includes: a heating tube, which is located on one side or both sides of the pole piece; a first temperature detector, whose probe is arranged to point to the pole piece; and an air blast dryer, whose air outlet is arranged to face the pole piece. Thus, by preheating the pole piece, the contact and infiltration of the molten metal and the pole piece are improved, which helps the coating with the metal material in the subsequent process and ensures the coating effect.

[0006] In some embodiments, a composite device is also included downstream of the coating device, and the composite device includes two composite rollers, which are respectively located on both sides of the pole piece; and an oiler, which is mounted above the composite roller on the side where the metal material is located. Therefore, under the rolling pressure of the two composite rollers, the bonding force between the pole piece and the metal material is increased, and under the action of oiling, the adhesion of the composite roller to the pole piece or the metal material is also prevented, thereby ensuring the stability of the composite device.

[0007] In some embodiments, it further comprises: a vent pipe interconnected with the top of the melting crucible, and a vent valve for opening and closing the vent pipe is provided on the vent pipe. Thus, during the metal melting process, inert gas can be introduced into the melting crucible through the vent pipe to protect the metal from being polluted by gas and moisture in the air, and to reduce defects such as oxidation of the metal; and after the metal is melted and stirred, the introduced inert gas can also remove impurity gases generated in the molten metal, thereby ensuring the purity of the metal material.

[0008] In some embodiments, the end of the vent pipe connected to the smelting crucible is inserted into the smelting crucible, and the end is located at the bottom of the smelting crucible. Therefore, the inert gas introduced helps to carry away the impurity gas generated in the molten metal during the rising process, thereby further ensuring the purity of the metal material.

[0009] In some embodiments, it also includes: a liquid outlet pipe, one end of which is connected to the smelting crucible and the other end is connected to the slit extrusion coating head; an air filling pipe, which is connected and connected to the liquid outlet pipe; and an air filling valve, which is arranged on the air filling pipe and is used to control the opening and closing of the air filling pipe. Therefore, after the lithium replenishment of the electrode is completed, the residual liquid remaining in the liquid outlet pipe can be removed by filling the air filling pipe to avoid solidification of the molten metal in the liquid outlet pipe, thereby increasing the maintenance cost.

[0010] In some embodiments, a heating module is provided inside the slot extrusion coating head, thereby further heating the molten metal to ensure smooth flow of the molten metal in the slot extrusion coating head, thereby reducing the occurrence of blockage of the molten metal in the slot extrusion coating head.

[0011] In some embodiments, it also includes a tension detection device, which is arranged in the discharge direction of the unwinding shaft and / or the feeding direction of the winding shaft, and the tension detection device includes an auxiliary support shaft, which is provided with two and is arranged at intervals at the bottom of the pole piece; a tension sensor shaft, which is located between the two auxiliary support shafts and pressed above the pole piece and can slide in the vertical direction of the line connecting the two auxiliary support shafts. Therefore, the function of the tension detector is to prevent the pole piece from being too tight or loose, and to ensure the pole piece's tape walking effect. Through the cooperation of the tension sensor shaft and the two auxiliary support shafts, the pole piece is continuously in a state of stable tension during the conveying movement, so that when passing through the preheating device, the pole piece is heated more evenly, ensuring the subsequent adsorption with the metal material; and it also ensures the stability of the pole piece state when the coating device is working, thereby further improving the uniformity of the metal material spreading.

[0012] In some embodiments, two coating devices are provided, and they act on both sides of the pole piece respectively. Thus, the coating device operates on the other side of the pole piece, thereby achieving double-sided lithium replenishment of the pole piece, greatly improving the lithium replenishment efficiency.

[0013] In some embodiments, the angle between the gas nozzle and the electrode coating surface is α, wherein 10°≤α≤80°. Thus, the angle between the gas nozzle and the electrode coating surface guides the wind direction of the wind knife, ensures the direction of the metal melt flow, and thus improves the accuracy of the coating thickness and uniformity operation.

[0014] In summary, the present application includes at least one beneficial technical effect:

[0015] 1. The problem of accuracy and purity of adding metallic lithium and alloys is solved; the use of a melting crucible can not only accurately proportion metals and metal alloys, but also the inert gas introduced during the melting process and after stirring can reduce the oxidation erosion on the surface of the molten metal, and can also remove the impurity gas inside the molten metal, further improving the purity of metallic lithium and alloys.

[0016] 2. Solved the problems of width, thickness and uniformity of lithium supplementation; adopted the structural mode of matching the slit extrusion coating head with the gas nozzle, and used the stable wind force of the wind knife to blow the metal material, so as to achieve the control of the width, thickness and uniformity of the metal material.

[0017] 3. It reduces the process addition and cost increase caused by the auxiliary substrate. The metal alloy is melted in a melting crucible, and then the slit extrusion coating head and the gas nozzle are used to achieve a one-time spraying of the metal alloy, avoiding the introduction of auxiliary substrates and the increase in costs caused by multiple processes.

[0018] 4. Improved efficiency: Due to the setting of the double coating device and the coordination of the steering shaft, bidirectional coating of the pole piece is achieved, which greatly increases the coating efficiency.

[0019] It should be understood that the contents described in the utility model summary are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure shows the overall structure of a pole piece lithium replenishing device provided by a preferred embodiment of the present invention;

[0021] Figure 2 A schematic structural diagram of an unwinding device in a pole piece lithium replenishing device provided by an embodiment of the present invention is shown;

[0022] Figure 3 A schematic structural diagram of a preheating device in a pole piece lithium replenishing device provided by an embodiment of the present invention is shown;

[0023] Figure 4 A schematic diagram of the structure of a melting device in a pole piece lithium replenishing device provided by an embodiment of the present invention is shown;

[0024] Figure 5 A schematic diagram of the structure of a coating device in a pole piece lithium replenishing device provided by an embodiment of the present invention is shown;

[0025] Figure 6 A schematic diagram of the structure of a composite device in a pole piece lithium replenishing device provided by an embodiment of the present invention is shown;

[0026] Figure 7 A schematic structural diagram of a winding device in a pole piece lithium replenishing device provided in an embodiment of the present invention is shown.

[0027] Explanation of symbols

[0028] 1. Unwinding device; 11. Unwinding shaft; 12. Unwinding correction device; 13. Tension detection device; 131. Auxiliary support shaft; 132. Tension sensor shaft; 2. Preheating device; 21. Heating tube; 22. First temperature detector; 23. Blast dryer; 3. Melting device; 31. Melting crucible; 311. Feeding port; 312. Agitator; 32. Heating element; 33. Ventilation pipe; 34. Ventilation valve; 35. Second temperature detector; 36. Liquid level detector; 37. Pressure force detector; 38, pressure air pipe; 39, pressure valve; 4, coating device; 41, liquid outlet pipe; 411, liquid outlet pipe valve; 412, liquid filter; 413, liquid flow detector; 42, slit extrusion coating head; 43, inflation pipe; 44, inflation valve; 45, gas nozzle; 46, pressurized air pipe; 47, pressurized air valve; 5, composite device; 51, composite roller; 52, oiler; 6, winding device; 61, winding shaft; 62, winding deviation correction device; 7, steering roller. DETAILED DESCRIPTION

[0029] Below, the preferred embodiments of the present utility model are described in detail with reference to the accompanying drawings.

[0030] The present invention provides a lithium supplement device for a pole piece, which includes an unwinding device 1, a preheating device 2, a melting device 3, a coating device 4, a compounding device 5, and a winding device 6. Through the coordination of several devices, the smelting of lithium metal or lithium alloy and the coating of both sides of the pole piece are realized, which not only solves the problem of the accuracy and purity of the addition of metal lithium and alloys; solves the problem of the width, thickness, and uniformity of the lithium supplement; and reduces the problem of the increase in process costs caused by the auxiliary substrate; and further improves the coating efficiency.

[0031] Refer to the following Figure 1-Figure 7 To describe a pole piece lithium replenishing device provided by an embodiment of the present invention.

[0032] Figure 1 The overall structure diagram of a pole piece lithium replenishing device provided by an embodiment of the present invention is shown. Figure 1 As shown, a pole piece lithium replenishing device provided in this embodiment includes an unwinding device 1, a preheating device 2, a melting device 3, a coating device 4, a compounding device 5, and a winding device 6 arranged in sequence. A plurality of steering rollers 7 are arranged between the unwinding device 1 and the winding device 6 for guiding, supporting, or flipping the pole piece. The unwinding device 1, the preheating device 2, the melting device 3, the coating device 4, the compounding device 5, and the winding device 6 are all supported and fixed by a frame, which is a conventional support structure and is not shown in the figure.

[0033] Figure 2 The structure diagram of the unwinding device 1 in the electrode lithium replenishing device provided by the embodiment of the present invention is shown. Figure 2As shown, the unwinding device 1 includes an unwinding shaft 11, an unwinding correction device 12, and a tension detection device 13; wherein the unwinding shaft 11 is horizontally arranged, and both ends thereof are rotatably connected to the frame; the unwinding correction device 12 includes guide blocks arranged on both sides of the pole piece, each guide block is slidably connected to the frame, and the spacing between the two guide blocks can be adjusted according to the width of the pole piece, so as to avoid the pole piece from deviating from the preset path, which is helpful for subsequent processes to operate the pole piece; the tension detection device 13 includes two auxiliary support shafts 131 located below the pole piece, the two auxiliary support shafts 131 are spaced and horizontally arranged, and both ends thereof are rotatably connected to the frames on both sides, and a tension sensor shaft 132 is arranged between the two auxiliary support shafts 131, the tension sensor shaft 132 is horizontally arranged and pressed above the pole piece, and both ends thereof are slidably connected to the frames on both sides, and the tension sensor shaft 132 can slide in the vertical direction of the line connecting the two auxiliary support shafts 131, so that the pole piece reaches a tensioned state, so as to improve the heating uniformity of the subsequent preheating device 2 and the coating accuracy of the coating device 4.

[0034] Figure 3 The schematic diagram of the structure of the preheating device 2 in the electrode lithium replenishing device provided by the embodiment of the present invention is shown. Figure 3 As shown, the preheating device 2 is arranged downstream of the unwinding device 1, and includes a heating tube 21 fixed to the frame. One or more heating tubes 21 may be provided and are located on one side or both sides of the electrode, and may be arranged equidistantly along the conveying direction of the electrode. The electrode can be quickly heated by the heating of the heating tube 21, thereby improving the contact and infiltration between the electrode and the molten metal, which helps to increase the bonding force with the metal; a first temperature detector 22 fixed to the frame is provided at the tail of the heating tube 21, and the probe of the first temperature detector 22 is arranged to point to the electrode, so that the real-time temperature of the electrode can be monitored and fed back, and the preset temperature of the heating tube 21 can be adjusted; a blast dryer 23 fixed to the frame is also provided at the tail of the heating tube 21, and one or more blast dryers 23 may be provided, and the air outlet is arranged toward the electrode, which is used to discharge the water evaporated by heat on the electrode to avoid affecting the subsequent processes.

[0035] A second temperature detector 35, a liquid level detector 36 and a pressure detector 37 are also fixed in the melting crucible 31, which are used to monitor the internal temperature, liquid level and internal pressure of the melting crucible 31. A pressure gas pipe 38 connected to and in communication with the melting crucible 31 is also provided on the top of the melting crucible 31, a pressure valve 39 is provided on the pressure gas pipe 38, and the other end of the pressure gas pipe 38 is connected to the inert gas source.

[0036] Figure 4 The schematic diagram of the structure of the melting device 3 in the electrode lithium replenishing device provided by the embodiment of the present invention is shown. Figure 4As shown, the melting device 3 includes a melting crucible 31, and a heating element 32 for heating the melting crucible 31 is fixed on the peripheral side of the melting crucible 31. Specifically, the heating element 32 can be heated by an electric heating wire or a silicon carbon rod to achieve the effect of melting the metal in the melting crucible 31. A feeding port 311 is provided on the top of the melting crucible 31, which can be used to feed metallic lithium and different alloy elements, and improve the performance of lithium-ion batteries by adding different alloy elements. Specifically, the alloy can include more than one element of Mg, Al, Cu, Zn, Sn, B, etc., and the addition mass of the alloy can be controlled to meet different alloy ratios. A stirrer 312 is provided in the melting crucible 31, and the stirrer 312 is rotatably connected to the top of the melting crucible 31, and a motor for driving the stirrer 312 to rotate is fixed on the top of the melting crucible 31. Since the stirrer 312 is a conventional structure, it will not be described in detail here. A vent pipe 33 is provided on the top of the melting crucible 31, one end of the vent pipe 33 is inserted into the melting crucible 31 and is located in the bottom area of ​​the melting crucible 31, and the other end is connected to the inert gas source, and the vent pipe 33 is located in the outer area of ​​the melting crucible 31 and is also connected to a vent valve 34. During the metal smelting process, inert gas can be injected into the melting crucible 31, wherein the inert gas can be argon, helium, neon, etc., to reduce the oxidation erosion of the metal by air, thereby reducing the formation of metal oxide impurities; and during the continuous stirring of the molten metal, the vent pipe 33 continuously introduces inert gas into the melting crucible 31 to reduce the impurity gas remaining in the molten metal, thereby improving the purity of the metal lithium or lithium alloy, and the impurity gas will be discharged through the feeding port 311.

[0037] Figure 5 The structure diagram of the coating device 4 in the electrode lithium replenishing device provided by the embodiment of the present invention is shown. Figure 5As shown, the coating device 4 includes a liquid outlet pipe 41, one end of which is connected to the bottom peripheral side of the melting crucible 31, and the other end is connected to a slit extrusion coating head 42. The middle part of the liquid outlet pipe 41 is also connected to a liquid outlet pipe valve 411, a liquid filter 412 and a liquid flow detector 413. The end of the above-mentioned slit extrusion coating head 42 is located directly above the electrode piece and is perpendicular to the plane where the electrode piece is located. A heating module is also arranged inside the slit extrusion coating head to maintain the state of the metal in the molten liquid in the slit extrusion coating head 42, so as to ensure the smooth flow of the molten metal in the slit extrusion coating head 42. When the slit extrusion coating head 42 is in extrusion operation, the feed port 311 and the vent valve 34 need to be closed, and then the pressure valve 39 and the liquid outlet pipe valve 411 are opened. At this time, an inert gas is injected into the pressure gas pipe 38. Under the action of pressure, the molten metal is pressed into the liquid outlet pipe 41 and filtered by the liquid filter 412 to enter the slit extrusion coating head 42 and be extruded. The temperature of the slit extrusion coating head 42 is controlled at 200-400°C to ensure the uniform outflow of the molten metal. In addition, an air filling pipe 43 is also provided on the liquid outlet pipe 41, one end of which is connected to the liquid outlet pipe 41 and communicated with the inside of the liquid outlet pipe 41, and the other end of the air filling pipe 43 is used to connect the gas source; an air filling valve 44 is also connected to the air filling pipe 43. When the slit extrusion coating head 42 discharges liquid, the inflation valve 44 is in a closed state. When the coating device 4 stops working, the liquid outlet pipe valve 411 can be closed, the inflation valve 44 can be opened, and gas can be filled into the inflation pipe 43 to clean the metal liquid residue inside the liquid outlet pipe 41 to prevent the residual metal melt from solidifying and causing blockage of the liquid outlet pipe 41.

[0038] The coating device 4 also includes a gas nozzle 45, and a pressurized air pipe 46 interconnected with the gas nozzle 45, and a pressurized air valve 47 is also connected to the pressurized air pipe 46. The gas nozzle 45 is mounted on the side of the slit extrusion coating head 42 facing the forward direction of the electrode, and the end of the gas nozzle 45 is tilted to point to the liquid falling area of ​​the slit extrusion coating head 42, and the angle between the gas nozzle 45 and the coating surface of the electrode is α, wherein 10°≤α≤80°. While the slit extrusion coating head 42 is discharging liquid, the pressurized air pipe 46 is connected to the high-pressure inert gas and sprayed out at high speed through the gas nozzle 45 to form a stable and continuous wind knife. The wind knife evenly blows away the dripping molten metal, so that the molten metal is evenly spread on the surface of the electrode. The thickness of the scraping is precisely controlled by controlling the flow rate of the liquid outlet pipe 41 and the pressure of the wind knife during scraping.

[0039] Figure 6 FIG. 5 is a schematic diagram showing the structure of a composite device 5 in a pole piece lithium replenishing device provided by an embodiment of the present invention. Figure 6As shown, one of the composite devices 5 is located downstream of the coating device 4 and includes two horizontally arranged composite rollers 51, both ends of which are slidably connected to the frame. Through the sliding of the two composite rollers 51, the gap between the two composite rollers 51 can be fine-tuned to achieve the effect of rolling the pole piece. During the displacement of the pole piece, the two composite rollers 51 rotate synchronously and squeeze the pole piece in the middle, thereby increasing the bonding force between the pole piece and the metal material. An oiler 52 is arranged above the composite roller 51 on the same side as the metal material, which is fixedly connected to the frame. During the rotation of the composite roller 51, the oiler 52 drips lubricating oil onto the composite roller 51 to wet the composite roller 51, thereby preventing the composite roller 51 from sticking to the pole piece or the metal material, and ensuring the stability of the composite device 5.

[0040] Figure 7 The schematic diagram of the structure of a winding device 6 in a pole piece lithium replenishing device provided by an embodiment of the present invention is shown. The winding device 6 includes a winding shaft 61 and a winding correction device 62; wherein the winding shaft 61 is horizontally arranged, and both ends thereof are rotatably connected to the frame, and one end thereof is also provided with a motor for driving the winding shaft 61 to rotate, thereby driving the pole piece to move and be wound on the winding shaft 61; the winding correction device 62 is arranged upstream of the winding shaft 61, and has the same structure as the unwinding correction device 12, and also includes two guide blocks and is located on both sides of the pole piece, and is slidably connected to the frame, and the spacing between the two guide blocks is adjusted by the width of the pole piece, thereby preventing the pole piece from deviating from the preset path; and the tension detection device 13 is also arranged at the winding device 6, and is located upstream of the winding correction device 62, and can control the tension sensor shaft 132 to slide in the vertical direction of the line connecting the two auxiliary support shafts 131, so that the pole piece reaches a tensioned state.

[0041] refer to Figure 1 As shown, the coating device 4 and the composite device 5 are provided with two, respectively, and are located on both sides of the melting crucible 31, wherein the steering roller 7 is provided with multiple between the unwinding shaft 11 and the winding shaft 61, and the pole piece is turned multiple times, so that the side of the pole piece not coated with metal material is turned upward and horizontally displaced, and the molten metal material is coated on the uncoated side of the pole piece under the action of the coating device 4, so that the double-sided lithium replenishment of the pole piece is achieved, which greatly improves the lithium replenishment effect. The composite device 5 is arranged downstream of the coating device 4, thereby further increasing the bonding force between the pole piece and the metal material.

[0042] The working process of the embodiment of the present application: the working environment needs to reach a dew point of ≤-50°C and a temperature of 20°C; open the feeding port 311 of the melting crucible 31, put the weighed metal lithium and other metal alloys into the melting crucible 31 according to the designed ratio, open the vent valve 34, introduce inert protective gas, start the heating element 32, set the temperature in the melting crucible 31 to be 400°C, and the heating rate is 10°C / min. When the metal lithium and other metal elements are completely integrated into a molten metal alloy mixture, turn on the agitator 312, continue to fill in inert protective gas, stir it, so that the alloy melt is further fully mixed and evenly, and remove the residual gas in the metal melt. The stirring time is 30min. Put the lithium pole coil to be supplemented on the unwinding shaft 11 of the unwinding device 1, adjust the position of the pole coil on the unwinding shaft 11, and pass through the unwinding correction device 12 and the tension detection device 13, the preheating device 2, the coating device 4, the composite device 5, and the tail coating device 4 and the composite device 5, and the winding device 6 in sequence. Set the unwinding tension to 60N, the winding tension to 90N, the belt speed to 10m / min, set the liquid pressure of the melting crucible 31 to 150mbar, keep the temperature of the slit extrusion coating head 42 at 200℃, and the air knife pressure to 0.1Mpa; set the preheating control temperature of the preheating device 2 to 130℃, heat the lithium electrode coil to be supplemented according to the set temperature under the action of the heating tube 21 and the first temperature detector 22, open the blast dryer 23, and discharge the baked water in time; start the pressure valve 39, pass the inert gas into the melting crucible 31, and open the liquid outlet valve 41 1. The alloy melt flows smoothly into the liquid outlet pipe 41 to the liquid filter 412. The filter diameter of the liquid filter 412 is 2um. Then, the alloy melt is transferred to the preheated electrode through the slit extrusion coating head 42. Then, a wind knife is formed through the gas nozzle 45. The metal melt is evenly scraped and cooled by the wind knife. After scraping, the lithium-replenished electrode passes through the composite roller 51 of the composite device 5 to roll the metal alloy and the electrode. Then, the uncoated surface of the electrode after lithium replenishment is turned upward, and coated and composited again, and finally rolled onto the winding shaft 61 through the winding device 6. After the lithium replenishment is completed, the liquid outlet pipe valve 411 is closed, the inflation pipe valve 44 is opened, and the remaining alloy melt in the liquid outlet pipe 41 is squeezed out and closed. Stop the heating of the preheating device 2, open the winding shaft 61, and unload the material.

[0043] In the description of this specification, the terms "connection", "installation", "fixation" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A lithium replenishing device for a pole piece, characterized in that: include: Unwinding reel (11); Reel (61); A melting device (3) comprising a melting crucible (31) for carrying molten metal, and a heating element (32) arranged on the periphery of the melting crucible (31); A coating device (4), comprising a slit extrusion coating head (42), which is interconnected and communicated with the smelting crucible (31), and the coating head end is located directly above the pole piece; A gas nozzle (45) is located on one side of the slit extrusion coating head (42) facing the advancing direction of the electrode piece, and its nozzle is tilted and points toward the liquid falling area of ​​the slit extrusion coating head 42; A pressure gas pipe (38) has one end connected to an external inert gas source and the other end connected to the melting crucible (31).

2. A pole piece lithium replenishing device according to claim 1, characterized in that: A preheating device (2) is also provided between the unwinding shaft (11) and the coating device (4), and the preheating device (2) comprises: A heating tube (21), which is located on one side or both sides of the electrode piece; A first temperature detector (22), the probe of which is arranged to point toward the pole piece; The air outlet of the blast dryer (23) is arranged toward the pole piece.

3. A pole piece lithium replenishing device according to claim 1, characterized in that: The invention also comprises a composite device (5) located downstream of the coating device (4), wherein the composite device (5) comprises Two composite rollers (51) are provided, and are respectively located on both sides of the pole piece; An oiler (52) is mounted above the composite roller (51) on the side where the metal material is located.

4. A pole piece lithium replenishing device according to claim 1, characterized in that: Also includes: A vent pipe (33) is interconnected with the top of the smelting crucible (31), and a vent valve (34) for opening and closing the vent pipe (33) is provided on the vent pipe (33).

5. A pole piece lithium replenishing device according to claim 4, characterized in that: Also includes: The end of the vent pipe (33) connected to the melting crucible (31) is inserted into the melting crucible (31), and the end thereof is located at the bottom of the melting crucible (31).

6. A pole piece lithium replenishing device according to claim 5, characterized in that: Also includes: A liquid outlet pipe (41), one end of which is connected to the smelting crucible (31) and the other end of which is connected to the slit extrusion coating head (42); an air filling tube (43), which is connected to and communicates with the liquid outlet tube (41); An inflation valve (44) is arranged on the inflation tube (43) and is used to control the opening and closing of the inflation tube (43).

7. The electrode lithium replenishing device according to claim 1, characterized in that: A heating module is arranged inside the slit extrusion coating head (42).

8. A pole piece lithium replenishing device according to claim 2, characterized in that: It also includes a tension detection device (13), which is arranged in the discharge direction of the unwinding shaft (11) and / or the feeding direction of the winding shaft (61), and the tension detection device (13) includes Two auxiliary support shafts (131) are provided and are arranged at intervals at the bottom of the pole piece; The tension sensor shaft (132) is located between the two auxiliary support shafts (131) and is pressed above the pole piece and can slide in a vertical direction along the line connecting the two auxiliary support shafts (131).

9. The electrode lithium replenishing device according to claim 1, characterized in that: The coating devices (4) are provided in two numbers and act on the two sides of the pole piece respectively.

10. The electrode lithium replenishing device according to claim 1, characterized in that: The included angle between the gas nozzle (45) and the pole piece coating surface is α, wherein 10°≤α≤80°.

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