Powder laying hot pressing dry method electrode manufacturing equipment

Abstract

The utility model is suitable for the technical field of battery manufacturing, and provides powder laying hot pressing dry method electrode manufacturing equipment. The equipment comprises a winding and unwinding device, a powder spreading device, a preheating device and a hot rolling device, the winding and unwinding device comprises an unwinding assembly and a winding assembly, and the unwinding assembly, the powder laying device, the preheating device, the hot rolling device and the winding assembly are sequentially connected. The method comprises the following steps: firstly, controlling a current collector to move through a winding and unwinding device, then paving an electrode powder material on the current collector through a powder paving device in an automatic blanking, rolling and powder paving manner, then preheating the electrode powder material through a preheating device, and treating the electrode powder material through a hot rolling device in a heating and pressurizing manner. And the high-density and compact lithium ion battery electrode plate is obtained. As no solvent participates in the manufacturing process, the manufacturing process is dry-method manufacturing, various problems in the existing wet-method electrode manufacturing process can be avoided, and the obtained electrode is uniform in thickness, compact and better in performance.

Description

Technical Field

[0001] The present application belongs to the field of battery manufacturing technology, and in particular relates to a powder-laying hot-pressing dry-process electrode manufacturing equipment. Background Art

[0002] Lithium-ion batteries have been widely used in portable electronic products such as mobile phones and computers, as well as electric vehicles, due to their high energy density, excellent cycle performance and long service life. These advantages make lithium-ion batteries an ideal source of power for these devices, meeting the needs of modern society for high efficiency, environmental protection and portability.

[0003] Traditional lithium-ion batteries are often mass-produced using a wet electrode manufacturing process to manufacture electrodes. During the manufacturing process, N-methylpyrrolidone solvent is required for homogenization and then drying. N-methylpyrrolidone solvent is toxic and corrosive, and there is a risk of affecting human health. Drying the solvent consumes a lot of energy, increasing the cost of electrode manufacturing.

[0004] Moreover, when lithium-ion batteries use sulfide solid electrolytes, since sulfide solid electrolytes are sensitive to water and polar organic solvents, they are affected by solvents during manufacturing, resulting in the destruction of the crystal structure and a decrease in lithium ion conductivity. In addition, during the drying process, the binder and the conductive agent will float on the surface and agglomerate due to capillary action and diffusion, which may cause the active material to precipitate, thereby causing electrode stratification. This stratification phenomenon will make the electrode easy to crack and reduce its structural stability.

[0005] Therefore, there is an urgent need for a lithium ion electrode manufacturing equipment that does not use solvents. Utility Model Content

[0006] The embodiment of the present application provides a powder-spreading hot-pressing dry electrode manufacturing equipment, which can manufacture lithium-ion battery electrodes without the involvement of solvents. It is a dry manufacturing method that can avoid many problems existing in the existing wet electrode manufacturing process. The manufactured electrodes are uniform in thickness, dense and have better performance.

[0007] In the first aspect, an embodiment of the present application provides a powder-spreading hot-pressing dry electrode manufacturing equipment, including: a winding and unwinding device, a powder-spreading device, a preheating device, and a hot rolling device; the winding and unwinding device includes a winding assembly and a winding assembly, and the winding assembly, the powder-spreading device, the preheating device, the hot rolling device and the winding assembly are connected in sequence; the winding assembly includes a feeding roller, a feeding roller guide roller and a feeding tension control roller, and the winding assembly includes a winding roller, a winding guide roller and a winding tension control roller; the current collector is placed on the feeding roller, and the current collector is connected to the winding roller after passing through the feeding roller guide roller, the feeding roller tension control roller, the powder-spreading device, the preheating device, the hot rolling device, the winding guide roller and the winding tension control roller; the powder-spreading device is used to spread the electrode powder material on the current collector when the current collector passes by; the preheating device is used to heat the electrode powder material laid on the current collector when the current collector passes by; the hot rolling device is used to hot roll-press the electrode powder material laid on the current collector when the current collector passes by.

[0008] In some possible embodiments, the powder spreading device includes: a powder bin, a powder feeding device, at least one powder spreading component, and a powder spreading platform; the powder feeding device is arranged in the powder bin, and the discharge port of the powder bin is arranged above the powder spreading platform, the powder feeding device includes a stirring roller, a stirring motor, a feeding roller and a feeding motor, the stirring roller is arranged in the powder bin near the inlet side, the feeding roller is arranged at the discharge port of the powder bin, the stirring roller and the stirring motor are powered connected, and the feeding motor and the feeding roller are powered connected; at least one powder spreading component is arranged at one end of the discharge port near the winding component, and the current collector is laid on the powder spreading platform; the powder spreading component includes a powder spreading roller and a powder spreading motor, the powder spreading roller and the powder spreading motor are powered connected, and the distance between the powder spreading roller and the powder spreading platform is 300-450μm.

[0009] In some possible implementations, the equipment also includes a mixing device; the mixing device includes a sealed cabin and a mixing assembly; a cabin door and a cylinder are provided on the sealed cabin, and the cylinder is dynamically connected to the cabin door for controlling the switch state of the cabin door; the sealed cabin also includes a vacuum pump, and the vacuum pump is connected to the sealed cabin through an air pipe; the mixing assembly includes a moving frame, a moving motor and at least one rotating material tank; the rotating material tank is provided on the moving frame, and the moving motor is dynamically connected to the moving frame for driving the moving frame to swing and rotate; the rotating material tank includes a material tank and a rotating motor, and the rotating motor is used to drive the material tank to rotate in the opposite direction of the rotation of the moving frame.

[0010] In some possible embodiments, the preheating device includes: a baking oven and a baking platform; the baking oven includes an outer shell and at least one baking lamp, the baking platform passes through the outer shell of the baking oven, the current collector is laid on the baking platform, and at least one baking lamp is arranged on the inner side of the outer shell for baking the electrode powder material on the current collector.

[0011] In some possible implementations, the number of the heating lamps is 5, and the 5 heating lamps are evenly distributed in the housing.

[0012] In some possible implementations, the temperature of each baking lamp is 150°C-180°C.

[0013] In some possible embodiments, the hot rolling device includes: at least one rolling assembly; the rolling assembly includes a guide roller, a guide plate, a differential roller machine, a roller temperature controller, a roller gap regulator, and a roller speed regulator; the roller temperature controller, the roller gap regulator, and the roller speed regulator are arranged on the differential roller machine, the roller temperature controller is used to control the roller surface temperature of the differential roller machine, the roller gap regulator is used to control the roller gap between the two rollers of the differential roller machine, and the roller speed regulator is used to control the rotational speed of each of the two rollers of the differential roller machine; the guide roller and the guide plate are arranged before the differential roller machine, and the collector enters between the two rollers of the differential roller machine after passing through the guide roller and the guide plate.

[0014] In some possible implementations, when there are multiple rolling assemblies, the last rolling assembly also includes: a hydraulic assembly; the hydraulic assembly is arranged on the differential roller machine, and is used to apply pressure to the two rollers of the differential roller machine, and the differential ratio of the differential roller machine is 1:1.

[0015] In some possible embodiments, the hot rolling device includes 6 rolling assemblies; the differential speed ratio of the differential speed roller of the first rolling assembly is 1:3.5 to 1:6.5, the roller gap between the two rollers is 250 μm to 300 μm, the rolling pressure is 2T to 4T, the rolling speed is 1 m to 3 m / min, and the roller surface temperature of the roller is 170°C to 190°C; the differential speed ratio of the differential speed roller of the second rolling assembly is 1:3 to 1: 5. The gap between the two rollers is 220μm to 250μm, the rolling pressure is 3T to 6T, the rolling speed is 1m to 3m per minute, and the roller surface temperature is 170℃ to 190℃; the differential speed ratio of the differential roller machine of the third rolling assembly is 1:2.5 to 1:3.5, the gap between the two rollers is 180μm to 220μm, the rolling pressure is 4T to 8 .... The roller surface temperature is 170℃ to 190℃; the differential speed ratio of the differential speed roller machine of the fourth rolling assembly is 1:2 to 1:3, the roller gap between the two rollers is 160μm to 180μm, the rolling pressure is 5T to 10T, the rolling speed is 1m to 3m per minute, and the roller surface temperature of the roller is 170℃ to 190℃; the differential speed ratio of the differential speed roller machine of the fifth rolling assembly is 1:1.5 to 1:2, and the roller gap between the two rollers is 160μm to 180μm, the rolling pressure is 5T to 10T, the rolling speed is 1m to 3m per minute, and the roller surface temperature of the roller is 170℃ to 190℃; The gap is 140μm to 160μm, the rolling pressure is 6T to 12T, the rolling speed is 1m to 3m per minute, and the roller surface temperature is 170℃ to 190℃; the differential speed ratio of the differential roller machine of the sixth rolling assembly is 1:1, the roller gap between the two rollers is 80μm to 140μm, the rolling pressure is 15T to 25T, the rolling speed is 1m to 3m per minute, and the roller surface temperature is 170℃ to 190℃.

[0016] In some possible implementations, a thickness measuring device is further provided between the hot rolling device and the winding assembly.

[0017] In the first aspect, the movement of the current collector is controlled by the unwinding and rewinding device, the electrode powder material is spread on the current collector by the powder spreading device by roller pressing, and then the electrode powder material is preheated by the preheating device, and then the electrode powder material is solidified, thinned, and compacted by the hot roller pressing device by heating and pressurizing to obtain a high-density and compact lithium-ion battery electrode sheet. Since the manufacturing process is dry manufacturing, no solvent is required, which can avoid various problems existing in the existing wet electronic manufacturing process, and the electrode thickness obtained is uniform and has better performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the structure of a powder-laying hot-pressing dry electrode manufacturing equipment provided in one embodiment of the present application;

[0020] Figure 2 A schematic diagram of the structure of a powder spreading device provided in one embodiment of the present application;

[0021] Figure 3 A schematic diagram of the structure of a powder bin and a powder feeding device in a powder spreading device provided in an embodiment of the present application;

[0022] Figure 4 A schematic diagram of the structure of a mixing device provided in one embodiment of the present application.

[0023] Legend: 11-powder spreading device; 111-powder bin; 1112-first side plate; 1113-second side plate; 1114-feeding port; 1115-discharging port; 112-powder unloading device; 1121-stirring roller; 1122-stirring motor; 1123-unloading roller; 1124-unloading motor; 1125-stirring part; 1126-unloading trough; 113-powder spreading component; 114-powder spreading platform; 12-preheating device; 121-housing; 122-heating lamp; 123- Baking platform; 13-hot roller pressing device; 14-unwinding assembly; 141-unwinding roller; 142-unwinding guide roller; 143-unwinding tension control roller; 15-winding assembly; 151-winding assembly including winding roller; 152-winding guide roller; 153-winding tension control roller; 16-current collector; 17-thickness measuring device; 18-mixing assembly; 181-moving frame; 182-moving motor; 183-rotating material tank; 1831-material tank; 1832-Teflon insulation ring. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described in conjunction with the drawings in the embodiment of the utility model. It should be understood that the drawings in the utility model only serve the purpose of illustration and description, and are not used to limit the scope of protection of the utility model. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in the utility model shows the operations implemented according to some embodiments of the utility model. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the utility model, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0025] In addition, the embodiments described in the present invention are only a part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiments of the utility model. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0027] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0028] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0029] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In the present invention, the unit N represents Newton and T represents ton.

[0030] Lithium-ion batteries have been widely used in portable electronic products such as mobile phones and computers, as well as electric vehicles, due to their high energy density, excellent cycle performance and long service life. These advantages make lithium-ion batteries an ideal source of power for these devices, meeting the needs of modern society for high efficiency, environmental protection and portability.

[0031] Traditional lithium-ion batteries are often mass-produced using a wet electrode manufacturing process to manufacture electrodes. During the manufacturing process, N-methylpyrrolidone solvent is required for homogenization and then drying. N-methylpyrrolidone solvent is toxic and corrosive, and there is a risk of affecting human health. Drying the solvent consumes a lot of energy, increasing the cost of electrode manufacturing.

[0032] However, when lithium-ion batteries use sulfide solid electrolytes, they are sensitive to water and polar organic solvents. During manufacturing, they are affected by solvents, which causes the crystal structure to be destroyed, resulting in a decrease in lithium ion conductivity. In addition, during the drying process, the binder and the conductive agent will float on the surface and agglomerate due to capillary action and diffusion, which may cause the active material to precipitate, thereby causing electrode stratification. This stratification phenomenon will make the electrode easy to crack and reduce its structural stability.

[0033] These problems existing in the wet electrode manufacturing process have limited the development of electrode surface capacity to a certain extent. Therefore, there is an urgent need for lithium-ion electrode manufacturing equipment that does not use solvents.

[0034] To solve this problem, the present application provides a powder-laying hot-pressing dry electrode manufacturing equipment.

[0035] Figure 1 A schematic diagram of the structure of a powder-laying hot-pressing dry electrode manufacturing equipment provided in one embodiment of the present application.

[0036] Reference Figure 1 , powder hot pressing dry electrode manufacturing equipment includes:

[0037] Winding and unwinding device, powder spreading device 11, preheating device 12, hot roller pressing device 13;

[0038] The unwinding and rewinding device comprises an unwinding assembly 14 and a rewinding assembly 15, wherein the unwinding assembly 14, the powder spreading device 11, the preheating device 12, the hot roller pressing device 13 and the rewinding assembly 15 are connected in sequence;

[0039] The unwinding assembly includes an unwinding roller 141, an unwinding guide roller 142 and an unwinding tension control roller 143, and the winding assembly includes a winding roller 151, a winding guide roller 152 and a winding tension control roller 153;

[0040] The current collector 16 is placed on the unwinding roller 141, and after passing through the unwinding guide roller 142, the unwinding tension control roller 143, the powder spreading device 11, the preheating device 12, the hot roller pressing device 13, the winding guide roller 152, and the winding tension control roller 153, the current collector 16 is connected to the winding roller 151;

[0041] The powder spreading device 11 is used to spread the electrode powder material on the current collector 16 when the current collector 16 passes by;

[0042] The preheating device 12 is used to heat the electrode powder material laid on the current collector 16 when the current collector 16 passes by;

[0043] The hot rolling device 13 is used to hot roll-press the electrode powder material laid on the current collector 16 when the current collector 16 passes by.

[0044] In some possible implementations, the material of the current collector may be aluminum, copper, or other metal composite materials, etc. As an example, when manufacturing the positive electrode of a lithium battery, the current collector may be an aluminum foil coil of a preset size, and when manufacturing the negative electrode of a lithium battery, the current collector may be a copper foil coil of a preset size.

[0045] Taking the aluminum foil coil as an example, the unwinding roller 141 can pass through the reel of the aluminum foil coil so that the aluminum foil coil is placed on the unwinding roller 141 .

[0046] As an example, a winding motor can be provided on the winding roller 151 to drive the winding roller 151 to rotate, thereby driving the current collector to move. In the present application, the current collector running speed can be set to 1-3m / min, and a correction component can also be provided on the unwinding guide roller 142 and the winding guide roller 152 to control the horizontal offset of the current collector to be maintained within the range of ±50μm. The unwinding tension control roller 143 and the winding tension control roller 153 can be adjusted in position so that the tension of the current collector is controlled within the range of 8N-15N.

[0047] In some possible implementations, when the unwinding assembly 14, the powder spreading device 11, the preheating device 12, the hot rolling device 13, and the winding assembly 15 are connected in sequence, the above components and devices may be fixedly connected by a connector, or the above devices or components may be simply arranged in order, and this application does not limit this. In actual application, the specific connection method is based on the ability to pass the current collector through each component and device in sequence.

[0048] In this embodiment, the movement of the current collector is controlled by the reeling and unreeling device, the electrode powder material is spread on the current collector by the powder spreading device by roller pressing, and then the electrode powder material is preheated by the preheating device, and then the electrode powder material is solidified, thinned, and compacted by the hot roller pressing device by heating and pressurizing to obtain a high-density and compact lithium-ion battery electrode sheet. Since the manufacturing process is dry manufacturing, no solvent is required, which can avoid various problems existing in the existing wet electronic manufacturing process, and the electrode thickness obtained is uniform and has better performance.

[0049] Figure 2 A schematic diagram of the structure of a powder spreading device provided in one embodiment of the present application; Figure 3 A schematic diagram of the structure of a powder bin and a powder feeding device in a powder spreading device provided in one embodiment of the present application.

[0050] In some possible implementations, reference is made to Figure 2The powder spreading device 11 includes: a powder bin 111, a powder unloading device 112, at least one powder spreading component 113, and a powder spreading platform 114. The powder unloading device 112 is arranged in the powder bin 111, and the discharge port of the powder bin 111 is arranged above the powder spreading platform 114. The powder unloading device 112 includes a stirring roller 1121, a stirring motor 1122, a unloading roller 1123 and a unloading motor 1124. The stirring roller 1121 is arranged in the powder bin 111 on one side close to the feeding port 1114, and the unloading roller 1123 is arranged at the discharge port 1115 of the powder bin 111. The stirring roller 1121 and the stirring motor 1122 are connected in power, and the unloading roller 1123 is connected in power to the unloading motor 1124.

[0051] In some possible implementations, reference is made to Figure 3 The powder bin 111 includes a first side plate 1112 and a second side plate 1113 that are arranged opposite to each other, and a front and rear cover plate that encloses a closed space with the first side plate 1112 and the first side plate 1113 .

[0052] The stirring motor 1122 is arranged on the first side plate 1112 of the powder bin 111, one end of the stirring roller 1121 is connected to the stirring motor 1122, and the other end passes through the first side plate 1112 and is connected to the bearing arranged on the first side plate 1113 of the powder bin 111; the unloading motor 1124 is arranged on the first side plate 1112 of the powder bin 111, one end of the unloading roller 1123 is connected to the stirring motor 1124, and the other end passes through the first side plate 1112 and is connected to the bearing arranged on the first side plate 1113 of the powder bin 111, and the unloading motor 1124 and the unloading roller 1123 are arranged below the stirring motor 1122 and the stirring roller 1121.

[0053] As an example, the stirring motor 1122 and the feeding motor 1124 may be reduction motors. A stirring portion 1125 may be provided on the stirring roller 1121, and the stirring portion 1125 may be an arc-shaped protrusion along the surface of the stirring roller 1121. The stirring motor 1122 drives the stirring roller 1121 to rotate in the powder bin 111, so that the electrode powder material in the hopper can be stirred more evenly, and the electrode powder material can be prevented from being stratified due to different particle sizes.

[0054] The unloading roller 1123 can be arranged at the discharge port 1115 at the bottom of the powder bin 111, with a portion located in the powder bin 111 and another portion passing through the discharge port 1115 to block the discharge port 1115. A plurality of unloading troughs 1126 matching the discharge port 1115 can be arranged on the unloading roller 1123. The unloading troughs 1126 of the portion of the unloading roller 1123 located in the powder bin 111 contain electrode powder materials. When the unloading roller 1123 is driven to rotate by the unloading motor 1124, if the unloading trough 1126 rotates to the outside of the discharge port 1115, the electrode powder materials contained in the unloading trough 1126 will fall onto the current collector below the feeding device 111, thereby completing the feeding.

[0055] At least one powder spreading component is arranged at one end of the discharge port close to the winding group 15, and the current collector is laid on the powder spreading platform 114; the powder spreading component 113 includes a powder spreading roller and a powder spreading motor, the powder spreading roller and the powder spreading motor are power-connected, and the distance between the powder spreading roller and the powder spreading platform is 300-450μm.

[0056] As an example, there may be two powder spreading assemblies 113 (respectively, the first powder spreading assembly and the second powder spreading assembly). The current collector is laid on the powder spreading platform and is driven by the reeling and unwinding device to pass through the discharge port of the powder feeding device, the first powder spreading assembly, and the second powder spreading assembly in sequence. The discharge port of the powder feeding device feeds the evenly stirred electrode powder material onto the current collector. The roller surface of the powder spreading roller of the first powder spreading assembly may be smooth, and the roller surface of the powder spreading roller of the second powder spreading assembly may be provided with patterns. The electrode powder material on the current collector is initially flattened by the powder spreading roller of the first powder spreading assembly, and then further flattened by the powder spreading roller of the second powder spreading assembly, so that the electrode powder material is evenly laid on the current collector. As an example, the rotation speed of the powder spreading roller of the first powder spreading assembly may be 10-20r / min, the rotation speed of the powder spreading roller of the second powder spreading assembly may be 5-10r / min, and the gap between the powder spreading roller and the powder spreading platform may be 300-450μm.

[0057] As an example, the stirring speed of the stirring roller can be 50r / min to continuously stir the electrode powder material to ensure that the electrode powder material is uniform. The electrode powder material is placed in the feeding trough under the action of gravity. When the feeding roller rotates, the electrode powder material contained in the feeding trough will be driven out of the powder bin and fall onto the current collector under the action of gravity to complete the feeding. As an example, the rotation speed of the feeding roller can be 100-200r / min.

[0058] In some possible implementations, the electrode powder material added to the powder bin needs to be fully mixed so that materials with different particle sizes and fluidities are mixed evenly. When mixing, the mixing device provided in the present application can be used.

[0059] In some possible implementations, the material mixing device includes a sealed cabin and a material mixing component.

[0060] As an example, the sealed cabin may be provided with a cabin door and a cylinder, wherein the cylinder is connected to the cabin door power for controlling the opening and closing state of the cabin door; the sealed cabin may also include a vacuum pump, which is connected to the sealed cabin through an air pipe.

[0061] When the air cylinder is controlled to close the hatch of the sealed cabin, the vacuum pump can be started to evacuate the sealed cabin, and when the vacuum degree reaches a certain value, mixing can be started through the mixing component. For example, when the vacuum degree reaches below 1mbar-2mbar, mixing can be started through the mixing component.

[0062] Figure 4 A schematic diagram of the structure of a mixing component provided in one embodiment of the present application.

[0063] The mixing assembly 18 includes a moving frame 181, a moving motor 182 and at least one rotating material tank 183; the rotating material tank 183 is arranged on the moving frame 181, and the moving motor 182 is connected to the moving frame 181 for driving the moving frame 181 to swing and rotate; the rotating material tank 183 includes a material tank 1831 and a rotating motor (arranged in the moving frame, not shown), and the rotating motor is used to drive the material tank 1831 to rotate in the opposite direction of the rotation of the moving frame 181.

[0064] In some possible embodiments, the material tank 1831 may include a connecting port, and a feeding port may be set on the top of the powder bin 111. The connecting port of the material tank 1831 is provided with an iris structure. When the connecting port of the material tank 1831 is inserted into the feeding port of the powder bin and rotated to tighten, the blades of the iris structure can be driven to open, so that the material tank 1831 is connected to the inside of the powder bin, and then the evenly mixed electrode powder material in the material tank 1831 falls into the powder bin 111 under the action of gravity.

[0065] In some possible implementations, the material tank 1831 can be removed from the moving frame 181 by a transfer device such as a robotic arm, an adsorption picking device, etc., which is arranged near the powder laying hot pressing dry electrode manufacturing equipment, and installed in the powder bin to realize automatic feeding.

[0066] It should be noted that since the material tank 1831 will rotate at high speed during mixing, this will cause the temperature of the material tank 1831 to increase. Since the material tank 1831 may be made of metal material, Teflon material can be used to insulate the material tank 1831, and a Teflon insulation ring 1832 can be set around the material tank 1831.

[0067] In some possible implementations, adding material to the material tank 1831 can also be achieved through the connection port. For example, the iris structure is moved by a corresponding mechanism so that the leaves of the iris structure open to expose the connection port, and the electrode powder material is added to the material tank 1831 through the connection port.

[0068] As an example, the electrode powder material includes three materials: electrode active material, binder and conductive agent powder, and the three materials can be loaded into the rotating material tank according to a preset ratio. In order to ensure the balance of the moving frame when rotating, the rotating material tank can be set to 3.

[0069] After the electrode powder material is loaded into the rotating material tank, the hatch of the sealed cabin can be closed by the cylinder control, and the sealed cabin can be evacuated by the vacuum pump. After the vacuum degree reaches below 2mbar, the motion motor is controlled to make the motion frame swing and rotate. As an example, the swinging and rotating speed of the motion frame can be 1000-2000r / min. At the same time, the rotating motor of each rotating material tank is controlled so that each rotating material tank rotates at 500-1000r / min in the opposite direction of the swinging rotation of the motion frame for 0.5 to 1 hour to complete the mixing. Among them, during mixing, the ambient humidity can be less than 30%RH and the temperature is between -10℃ and 40℃.

[0070] In some possible implementations, the mixing process may adopt staged mixing. That is, multiple stages with different rotation speeds and durations may be set according to factors such as the particle size difference of the materials, the material fluidity, and the material composition, so as to achieve different mixing effects. For example, the worse the material fluidity, the higher the rotation speed and the longer the time required; the more material components to be mixed, the more stages required.

[0071] In some possible implementations, since the high-speed mixing process may cause the material to heat up, it is necessary to dissipate heat through a staged mixing method.

[0072] As an example, the first stage can be set to use low-speed mixing, for example, the swinging speed of the moving frame is set to 1000r / min, and the rotation speed of the rotating tank is 500r / min, which lasts for 5min; the second stage can be set to use medium-speed mixing, for example, the swinging speed of the moving frame is set to 1500r / min, and the rotation speed of the rotating tank is 750r / min, which lasts for 10min; the third stage can be set to use high-speed mixing, for example, the swinging speed of the moving frame is set to 2000r / min, and the rotation speed of the rotating tank is 1000r / min, which lasts for 15min.

[0073] In some possible implementations, reference is made to Figure 1 The preheating device 12 includes: a baking oven and a baking platform 123; the baking oven includes an outer shell 121 and at least one baking lamp 122, the baking platform 123 passes through the outer shell of the baking oven, the collector is laid on the baking platform 123, and at least one baking lamp 122 is arranged on the inner side of the outer shell for baking the electrode powder material on the collector.

[0074] In some possible implementations, when the current collector with the electrode powder material is passed through the preheating device 12, the electrode powder material needs to be heated to above 150°C. In order to ensure the temperature of the electrode powder material, refer to Figure 1 The number of baking lamps can be 5, and the 5 baking lamps are evenly distributed in the shell, and the temperature of each baking lamp is 150℃-180℃.

[0075] In some possible embodiments, the hot rolling device includes: at least one rolling assembly; the rolling assembly includes a guide roller, a guide plate, a differential roller machine, a roller temperature controller, a roller gap regulator, and a roller speed regulator; the roller temperature controller, the roller gap regulator, and the roller speed regulator are arranged on the differential roller machine, the roller temperature controller is used to control the roller surface temperature of the differential roller machine, the roller gap regulator is used to control the roller gap between the two rollers of the differential roller machine, and the roller speed regulator is used to control the rotational speed of each of the two rollers of the differential roller machine; the guide roller and the guide plate are arranged before the differential roller machine, and the collector enters between the two rollers of the differential roller machine after passing through the guide roller and the guide plate.

[0076] The current collector with the flat powder enters the differential roller machine through the guide rollers and guide plates for high temperature and high pressure curing. The guide rollers and guide plates can ensure that the current collector enters the differential roller machine smoothly, ensuring that no electrode powder material is shaken off.

[0077] The problem of powder material sticking to the roller can be effectively solved by rolling with a differential speed roller machine. The roller temperature controller needs to ensure that the roller surface temperature of the differential speed roller machine reaches above 180°C during rolling to ensure the high temperature effect.

[0078] The roll gap regulator is used to adjust the roll gap between the rolls to ensure a certain pressure, and the roll speed regulator is used to adjust the roll pressing speed to ensure the roll pressing quality.

[0079] In some possible implementations, when there are multiple rolling assemblies, the last rolling assembly also includes: a hydraulic assembly; the hydraulic assembly is arranged on the differential roller machine, and is used to apply pressure to the two rollers of the differential roller machine, and the differential ratio of the differential roller machine is 1:1.

[0080] In some possible implementations, when there are multiple rolling assemblies, the front multi-stage rolling assembly is mainly used to gradually reduce the roller gap, increase the pressure, achieve secondary high temperature and high pressure curing, enhance the curing effect, and perform thinning by reducing the roller gap.

[0081] The last stage of rolling assembly is used to compact and ensure the surface flatness. Compared with the previous rolling assembly, the differential speed ratio of the differential roller machine can be set to 1:1, and the roller gap can be adjusted to the target pole piece thickness to achieve synchronous rolling to ensure surface flatness and compact the pole piece to the target thickness. At the same time, the pressure between the two rollers of the differential roller machine is increased through the hydraulic device to ensure that the electrode powder material on the pole piece is further compacted, improve the density of the pole piece, and obtain the target pole piece.

[0082] In some possible implementations, the hot rolling device is a multi-stage rolling device, referring to Figure 1 , the hot rolling device includes 6 rolling assemblies, as an example:

[0083] The differential speed ratio of the differential roller machine of the first rolling assembly is 1:3.5, the roller gap between the two rollers is 275 μm, the rolling pressure is 3T, the rolling speed is 2 meters per minute, and the roller surface temperature of the roller is 180°C.

[0084] The differential speed ratio of the differential roller machine of the second rolling assembly is 1:3, the roller gap between the two rollers is 235 μm, the rolling pressure is 4.5 T, the rolling speed is 2 meters per minute, and the roller surface temperature of the roller is 180°C.

[0085] The differential speed ratio of the differential roller machine of the third rolling assembly is 1:2.5, the roller gap between the two rollers is 200 μm, the rolling pressure is 6 T, the rolling speed is 2 meters per minute, and the roller surface temperature of the roller is 180°C.

[0086] The differential ratio of the differential roller machine of the fourth rolling assembly is 1:2, the roller gap between the two rollers is 170μm, the rolling pressure is 7.5T, the rolling speed is 2 meters per minute, and the roller surface temperature is 180℃.

[0087] The differential speed ratio of the differential roller machine of the fifth rolling assembly is 1:1.5, the roller gap between the two rollers is 150μm, the rolling pressure is 9T, the rolling speed is 2 meters per minute, and the roller surface temperature of the roller is 180℃.

[0088] The differential ratio of the differential roller of the sixth rolling assembly is 1:1, the roller gap between the two rollers is 110 μm, the rolling pressure is 20 T, the rolling speed is 2 meters per minute, and the roller surface temperature is 180°C.

[0089] In some possible implementations, the hot roller pressing device may further include a residual material recovery tank, which may be disposed below the differential speed roller machine to receive the electrode powder material scattered during the rolling process.

[0090] In some possible implementations, a thickness measuring device 17 is further provided between the hot rolling device and the winding assembly.

[0091] As an example, the thickness measuring device 17 can use optical fiber to measure the thickness of the pole piece. The thickness of the pole piece is measured by optical fiber laser, and the thickness of the prepared pole piece is obtained by the feedback value. The thickness error is ±5μm.

[0092] The powder-laying hot-pressing dry electrode manufacturing equipment can control the winding and unwinding device to move the current collector from the winding component to the unwinding component at a speed of 1 to 3 meters per minute, and the tension of the current collector during movement ranges from 8N ​​to 15N; the electrode powder material with a thickness of 300μm to 450μm is laid on the current collector through the powder-laying device; the electrode powder material is heated through the preheating device to make the temperature of the electrode powder material greater than or equal to 150°C; the electrode powder material laid on the current collector is rolled at 170°C to 190°C through the hot rolling device to obtain the target electrode sheet.

[0093] In some possible implementations, when the hot rolling device includes a plurality of rolling assemblies, the electrode powder material laid on the current collector is rolled through each rolling assembly in turn at 170° C. to 190° C. to obtain a target electrode sheet.

[0094] Among them, the electrode powder material is rolled multiple times to ensure that the electrode powder material on the electrode sheet is gradually thinned and further compacted, thereby reducing the thickness of the electrode sheet, increasing the density of the electrode sheet, and improving the quality of the electrode sheet.

[0095] In some possible implementations, the thickness of the target pole piece is measured by a thickness measuring device, and the measured thickness of the target pole piece is displayed.

[0096] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0097] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited to this. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A powder-laying hot-pressing dry electrode manufacturing equipment, characterized in that: include: Winding and unwinding device, powder spreading device, preheating device, hot roller pressing device; The unwinding and rewinding device comprises an unwinding assembly and a rewinding assembly, wherein the unwinding assembly, the powder spreading device, the preheating device, the hot rolling device and the rewinding assembly are connected in sequence; The unwinding assembly includes an unwinding roller, an unwinding guide roller and an unwinding tension control roller, and the winding assembly includes a winding roller, a winding guide roller and a winding tension control roller; The current collector is placed on the unwinding roller, and after passing through the unwinding guide roller, the unwinding tension control roller, the powder spreading device, the preheating device, the hot roller pressing device, the winding guide roller, and the winding tension control roller, the current collector is connected to the winding roller; The powder spreading device is used to spread the electrode powder material on the current collector when the current collector passes by; The preheating device is used to heat the electrode powder material laid on the current collector when the current collector passes by; The hot rolling device is used to hot roll-press the electrode powder material laid on the current collector when the current collector passes by.

2. The device according to claim 1, characterized in that: The powder spreading device comprises: a powder bin, a powder feeding device, at least one powder spreading component, and a powder spreading platform; The powder feeding device is arranged in the powder bin, the discharge port of the powder bin is arranged above the powder spreading platform, the powder feeding device comprises a stirring roller, a stirring motor, a feeding roller and a feeding motor, the stirring roller is arranged in the powder bin near the feeding port, the feeding roller is arranged at the discharge port of the powder bin, the stirring roller is connected to the stirring motor, and the feeding motor is connected to the feeding roller; The at least one powder spreading assembly is arranged at one end of the discharge port close to the winding assembly, and the current collector is laid on the powder spreading platform; The powder spreading component comprises a powder spreading roller and a powder spreading motor, the powder spreading roller and the powder spreading motor are power-connected, and the distance between the powder spreading roller and the powder spreading platform is 300-450 μm.

3. The device according to claim 2, characterized in that: Also includes a mixing device; The mixing device comprises a sealed cabin and a mixing component; The sealed cabin is provided with a cabin door and a cylinder, and the cylinder is connected to the cabin door by power to control the opening and closing state of the cabin door; The sealed cabin also includes a vacuum pump, and the vacuum pump is connected to the sealed cabin through an air pipe; The mixing assembly includes a moving frame, a moving motor and at least one rotating material tank; The rotating material tank is arranged on the moving frame, and the moving motor is connected to the moving frame for driving the moving frame to swing and rotate; The rotating material tank comprises a material tank and a rotating motor, and the rotating motor is used to drive the material tank to rotate in the opposite direction of the rotation of the moving frame.

4. The device according to claim 1, characterized in that: The preheating device comprises: Baking oven, baking platform; The baking oven comprises an outer shell and at least one baking lamp. The baking platform passes through the outer shell of the baking oven. The current collector is laid on the baking platform. The at least one baking lamp is arranged on the inner side of the outer shell for baking the electrode powder material on the current collector.

5. The device according to claim 1, characterized in that: The hot rolling device comprises: at least one rolling assembly; The rolling assembly includes a guide roller, a guide plate, a differential speed roller machine, a roller temperature controller, a roller gap regulator, and a roller speed regulator; The roller temperature controller, roller gap regulator, and roller speed regulator are arranged on the differential speed roller machine. The roller temperature controller is used to control the roller surface temperature of the differential speed roller machine. The roller gap regulator is used to control the roller gap between the two rollers of the differential speed roller machine. The roller speed regulator is used to control the rotation speed of each of the two rollers of the differential speed roller machine. The guide roller and the guide plate are arranged before the differential roller machine. After the current collector passes through the guide roller and the guide plate, it enters between the two rollers of the differential roller machine.

6. The device according to claim 5, characterized in that When there are multiple rolling assemblies, the last rolling assembly further includes: a hydraulic assembly; The hydraulic assembly is arranged on the differential roller machine and is used to apply pressure to the two rollers of the differential roller machine. The differential speed ratio of the differential roller machine of the last rolling assembly is 1:

1.

7. The device according to claim 6, characterized in that The hot rolling device includes 6 rolling assemblies; The differential speed ratio of the differential roller of the first rolling assembly is 1:3.5 to 1:6.5, the roller gap between the two rollers is 250 μm to 300 μm, the rolling pressure is 2T to 4T, the rolling speed is 1m to 3m / min, and the roller surface temperature of the roller is 170°C to 190°C; The differential speed ratio of the differential roller of the second rolling assembly is 1:3 to 1:5, the roller gap between the two rollers is 220 μm to 250 μm, the rolling pressure is 3T to 6T, the rolling speed is 1m to 3m / min, and the roller surface temperature of the roller is 170°C to 190°C; The differential speed ratio of the differential roller of the third rolling assembly is 1:2.5 to 1:3.5, the roller gap between the two rollers is 180 μm to 220 μm, the rolling pressure is 4 T to 8 T, the rolling speed is 1 m to 3 m per minute, and the roller surface temperature of the roller is 170° C. to 190° C.; The differential speed ratio of the differential roller of the fourth rolling assembly is 1:2 to 1:3, the roller gap between the two rollers is 160 μm to 180 μm, the rolling pressure is 5 T to 10 T, the rolling speed is 1 m to 3 m per minute, and the roller surface temperature of the roller is 170° C. to 190° C.; The differential speed ratio of the differential roller of the fifth rolling assembly is 1:1.5 to 1:2, the roller gap between the two rollers is 140 μm to 160 μm, the rolling pressure is 6 T to 12 T, the rolling speed is 1 m to 3 m per minute, and the roller surface temperature of the roller is 170° C. to 190° C.; The differential ratio of the differential roller of the sixth rolling assembly is 1:1, the roller gap between the two rollers is 80μm to 140μm, the rolling pressure is 15T to 25T, the rolling speed is 1m to 3m per minute, and the roller surface temperature is 170℃ to 190℃.

8. The equipment according to any one of claims 1 to 7, characterized in that: A thickness measuring device is also provided between the hot rolling device and the winding assembly.

9. The device according to claim 4, characterized in that: The number of the heating lamps is 5, and the 5 heating lamps are evenly distributed in the housing.

10. The device according to claim 4 or 9, characterized in that: The temperature of the baking lamp is 150°C to 180°C.

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