A dry electrode film roll-pressing and compounding device and a compounding method

Abstract

The present application relates to the technical fields of dry electrode film preparation, and discloses a dry electrode film roll pressing composite equipment, which comprises a pre-composite non-powered unwinding assembly, a hot pressing roller assembly with a hot pressing passing gap and two separator film unwinding assemblies; the pre-composite non-powered unwinding assembly comprises a current collector unwinding shaft, a pre-composite passing roller and two dry film unwinding shafts arranged in sequence along a second direction, a dry film passing gap is formed between the two dry film unwinding shafts, a tangent line of the outer diameter of the pre-composite passing roller and a midpoint of the dry film passing gap along the second direction are sequentially arranged along a first direction and projectively coincide, and the two separator film unwinding assemblies are sequentially arranged along the second direction. The dry electrode film roll pressing composite equipment avoids the dry film attached to the current collector due to the air flow disturbance or tension fluctuation of the protective separator film, at the same time, avoids the wrinkle of the separator film, effectively reduces the defect rate, and improves the roll pressing composite quality and the stability of the roll pressing composite operation.

Description

Technical Field

[0001] This invention relates to the field of dry electrode film preparation technology, and specifically to a dry electrode film roll forming equipment. Background Technology

[0002] In recent years, with the widespread application of lithium-ion batteries in new energy vehicles, energy storage systems, and consumer electronics, electrode preparation technology has gradually shifted from traditional wet coating to dry film formation and roll forming composite processes. Dry electrode films, which do not require solvents or drying processes, have advantages such as being environmentally friendly, having low energy consumption, and having short processing times, and have become an important development direction in the lithium battery manufacturing field. In this process, dry films are usually formed by physical calendering of conductive agents, active materials, and binder components, and then double-sided composited with a metal current collector to form an electrode sheet. Roll forming composite equipment plays a key role in this process, determining the bonding accuracy between the dry film and the current collector, the interface density, and the surface quality of the electrode sheet. It is the core equipment to ensure the consistency of dry electrode performance and production stability.

[0003] However, in existing dry electrode film roll forming equipment, there are common problems such as insufficient alignment accuracy and uneven tension between the dry film and the current collector before they merge, resulting in poor coating accuracy of the dry film on the current collector surface. In addition, the traditional equipment usually adopts a simple series unwinding and guide roller structure for the film belt path design. In order to avoid the dry film adhering to the surface of the hot press roller and making it difficult to clean, a release liner is used to protect the current collector with the dry film attached. However, the release liner is often affected by airflow disturbance, electrostatic adsorption or tension fluctuation during the conveying process, and often drifts and wrinkles. This makes it difficult to stably control the bonding surface distance between the hot press rollers. When wrinkles occur, the machine needs to be stopped to adjust the release liner. This not only affects the pressure distribution and interfacial density of the composite material, causing composite defects, but also affects the stability of the roll forming operation, thus affecting the efficiency of continuous roll forming. Summary of the Invention

[0004] The purpose of this invention is to provide a dry electrode film roll forming equipment and method, which avoids the protective separator from being knocked off the dry film attached to the current collector due to airflow disturbance or tension fluctuation. At the same time, it avoids wrinkles in the separator, effectively reduces the defect rate, and improves the quality and stability of roll forming operation.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] Design a dry electrode film roll pressing composite equipment, including a pre-composite non-powered unwinding assembly, a hot pressing roller assembly with a hot pressing gap, and two separator film unwinding assemblies;

[0007] The pre-composite non-powered unwinding assembly includes a current collector unwinding shaft, a pre-composite guide roller, and two dry film unwinding shafts arranged sequentially along the second direction. A dry film gap is formed between the two dry film unwinding shafts. The tangent of the outer diameter of the pre-composite guide roller and the midpoint of the dry film gap along the second direction are arranged sequentially along the first direction and their projections coincide.

[0008] Two separator film unwinding assemblies are arranged sequentially along the second direction, and their output ends are both located at the output end of the dry film unwinding shaft along the first direction. The two separator film unwinding assemblies are arranged symmetrically about the midpoint of the dry film gap along the second direction along the straight line of the first direction.

[0009] It also includes two adsorption plates, which are respectively arranged corresponding to two separator film unwinding assemblies and are respectively located between the corresponding separator film unwinding assembly and the hot pressing gap. One of the adsorption plates is arranged parallel to the conveying path of the corresponding separator film for bonding with the separator film. The adsorption plate has a negative pressure hole on the plate surface for bonding with the separator film.

[0010] The hot press roller assembly is used to perform a hot pressing process on the material entering the hot press gap.

[0011] Optionally, the adsorption plate includes a plate body, one of the plate surfaces of which is arranged parallel to the conveying path of the corresponding isolation membrane for bonding with the isolation membrane. The negative pressure hole is opened on the surface of the plate body facing the isolation membrane. An adsorption cavity communicating with the negative pressure hole is opened inside the plate body. A fan cylinder is connected to the side of the plate body through a pipe, and the input end of the fan cylinder is connected to the adsorption cavity.

[0012] Optionally, the plate body has an air inlet hole communicating with the adsorption chamber on the surface away from the isolation membrane. The inner wall of the adsorption chamber is provided with an air guide tube, and one end of the air guide tube covers the negative pressure hole. The diameter of the opening at the end of the air guide tube that covers the negative pressure hole gradually decreases along the extension direction to the diameter of the opening at the other end. A fan is provided inside the fan tube.

[0013] Optionally, the hot press roller assembly includes a pushing mechanism and two hot press roller mechanisms arranged sequentially along a second direction. The telescopic end of the pushing mechanism is connected to the fixed end of one of the hot press roller mechanisms, and is used to push one of the hot press roller mechanisms closer to the other hot press roller mechanism along the second direction. The hot press gap is formed between the two hot press roller mechanisms. The rotating ends of the two hot press roller mechanisms rotate towards each other or away from each other, and are used to perform a hot pressing process on the material within the hot press gap.

[0014] Optionally, the hot press roller mechanism includes a driving member and a composite roller arranged sequentially along a third direction. The output end of the driving member is connected to one end of the composite roller to drive the composite roller to rotate. The fixed end of the driving member and the other end of the composite roller are both fixedly connected to the telescopic end of the pushing mechanism.

[0015] Optionally, the composite roller includes a hot press roller body extending in a third direction, a receiving cavity, a support roller body, a heating cavity, a heating tube, and multiple heat-conducting fins. One end of the hot press roller body is connected to the output end of the drive component, and the other end is rotatably connected to the outer surface of the support roller body through an opening groove. The end of the support roller body away from the hot press roller body is connected to the telescopic end of the pushing mechanism.

[0016] Optionally, the receiving cavity is formed in the hot press roller body to contain heat transfer oil, the heating cavity is formed in the support roller body, the heating end of the heating tube is set in the heating cavity, a plurality of heat transfer fins are circumferentially arrayed on the inner wall of the heating cavity, and the other ends of the plurality of heat transfer fins abut against the heating end of the heating tube. The end face of the support roller body is fixedly connected to an air inlet pipe and an air outlet pipe communicating with the heating cavity, and the input end of the air inlet pipe is connected to the output end of the fan cylinder.

[0017] Optionally, a winding assembly is also included, comprising a first winding roller, a second winding roller, a third winding roller, a first guide roller, a second guide roller, and two heat dissipation pipes. The first winding roller, the first guide roller, the second guide roller, and the second winding roller are arranged sequentially along a second direction. The third winding roller is located below the second guide roller. The first guide roller and the second guide roller are rotatably connected to the two heat dissipation pipes, respectively. One end of each heat dissipation pipe is fixedly connected to a heat dissipation air pipe, which overlaps with the heat dissipation pipe along a first direction. The surface of the heat dissipation air pipe has heat dissipation openings facing the composite material.

[0018] Optionally, the device also includes a housing, which is equipped with a two-position three-way solenoid valve connected in series in the circuit of the drive unit. The two-position three-way solenoid valve is provided with a first outlet, a second outlet, and an inlet. The inlet of the two-position three-way solenoid valve is connected to the output end of the fan casing through a pipe, the first outlet is connected to the input end of the air inlet pipe through a pipe, and the second outlet is connected to the input end of the cooling air pipe through a pipe.

[0019] A dry electrode film roll forming method, employing the dry electrode film roll forming equipment described above, includes:

[0020] A current collector is sleeved on the current collector unwinding shaft. The current collector is unwound through the current collector unwinding shaft and guided to the pre-composite roller. The current collector passes through the dry film gap between the two dry film unwinding shafts under its own weight. The dry film on the dry film unwinding shaft is attached to the current collector to obtain the pre-composite film.

[0021] The pre-composite film passes through a separator film unwinding assembly with a separator film attached. The two separator film unwinding assemblies unwind the separator film so that the two separator films are located on both sides of the pre-composite film. The adsorption plate is attached to the corresponding separator film until the two separator films and the pre-composite film are sent into the hot pressing gap for hot pressing to obtain the composite material.

[0022] This invention provides a dry electrode film roll forming equipment, which has the following advantages:

[0023] This dry electrode film roll lamination equipment and method involves unwinding the current collector. After passing through a pre-lamination roller, the current collector enters the dry film gap. The projection of the tangent of the pre-lamination roller's outer diameter coincides with the center point of the dry film gap, ensuring a stable and symmetrical stretching path for the dry film before it merges with the current collector. This allows for precise alignment and initial lamination of the dry film onto the current collector, guaranteeing coating accuracy and consistency on both sides of the current collector and reducing current collector misalignment and breakage caused by tension differences. Subsequently, the separator films led out by the two separator film unwinding assemblies are subjected to negative pressure as they pass through their respective adsorption plates. The adsorption force generated by the pores tightly flattens the membrane and also produces a certain tension, which can eliminate the drifting and wrinkling of the separator membrane during the conveying process until it is introduced into the hot pressing gap of the hot pressing roller assembly. In the hot pressing gap, the dry membrane and the current collector are hot-pressed and compounded. The negative pressure holes of the adsorption plate can effectively suppress the drifting of the separator membrane through the negative pressure airflow, ensuring that the surface spacing and flatness remain stable before entering the hot pressing gap. This avoids bubbles and wrinkles caused by the separator membrane during hot pressing, effectively reducing the defect rate. This not only improves the quality and consistency of roller pressing compounding, but also improves the stability of roller pressing compounding operation. Attached Figure Description

[0024] Figure 1 This is a front cross-sectional view of the composite roller in this invention.

[0025] Figure 2 This is a three-dimensional structural diagram of the dry electrode film roll forming composite equipment of the present invention;

[0026] Figure 3 In this invention Figure 2 A magnified structural diagram of part A;

[0027] Figure 4 This is a side cross-sectional view of the hot press roller mechanism in this invention;

[0028] Figure 5 This is a front cross-sectional view of the adsorption plate in this invention.

[0029] Figure 6 This is a side cross-sectional view of the heat dissipation pipe in this invention.

[0030] In the diagram: 10. Pre-composite non-powered unwinding assembly; 11. Current collector unwinding shaft; 12. Pre-composite guide roller; 13. Dry film unwinding shaft; 20. Separator film unwinding assembly; 30. Hot press roller assembly; 31. Hot press roller mechanism; 311. Drive component; 312. Composite roller assembly; 3121. Hot press roller body; 3122. Receiving cavity; 3123. Support roller body; 3124. Heating cavity; 3125. Heating tube; 3126. Heat-conducting fins 3127. Air inlet pipe; 3128. Air outlet pipe; 32. Pushing mechanism; 40. Adsorption plate; 41. Negative pressure hole; 42. Plate body; 43. Air inlet hole; 44. Air guide tube; 45. Fan tube; 46. Fan; 50. Rewinding assembly; 51. First rewinding roller; 52. Second rewinding roller; 53. Third rewinding roller; 54. First guide roller; 55. Second guide roller; 56. Heat dissipation pipe; 57. Heat dissipation pipe; 70. Machine body. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0032] Please see Figures 1 to 6 The present invention provides a technical solution: a roll forming lamination equipment, specifically applied in the roll forming lamination of dry electrode films, with the aim of improving the lamination accuracy and reducing the impact of the drifting of the isolation membrane set to avoid dirty rollers on the lamination quality of the electrode film.

[0033] Please see Figures 1 to 6 The present invention provides a technical solution: a dry electrode film roll forming equipment, comprising a pre-composite non-powered unwinding assembly 10, a hot press roller assembly 30 with a hot press gap, and two isolation film unwinding assemblies 20.

[0034] The pre-composite non-powered unwinding assembly 10 includes a current collector unwinding shaft 11, a pre-composite guide roller 12, and two dry film unwinding shafts 13 arranged sequentially along the second direction. A dry film gap is formed between the two dry film unwinding shafts 13. The tangent of the outer diameter of the pre-composite guide roller 12 and the midpoint of the dry film gap along the second direction are arranged sequentially along the first direction and their projections coincide.

[0035] Two separator film unwinding assemblies 20 are arranged sequentially along the second direction, and their output ends are both located at the output end of the dry film unwinding shaft 13 along the first direction. The two separator film unwinding assemblies 20 are arranged symmetrically about the midpoint of the dry film gap along the second direction along the straight line of the first direction.

[0036] It also includes two adsorption plates 40, which are respectively set to correspond to two isolation film unwinding assemblies 20 and are respectively located between the corresponding isolation film unwinding assembly 20 and the hot pressing gap. One of the adsorption plates 40 is set parallel to the conveying path of the corresponding isolation film for bonding with the isolation film. The adsorption plate 40 has a negative pressure hole 41 on the plate surface for bonding with the isolation film.

[0037] The hot press roller assembly 30 is used to perform a hot pressing process on the material entering the hot press gap;

[0038] The current collector is drawn out from the current collector unwinding shaft 11 and passes through the pre-composite roller 12. That is, the dry film unwound by the two dry film unwinding shafts 13 or the dry film material on the dry film unwinding shafts 13 adheres to the surface of the current collector. The two dry film unwinding shafts 13 are symmetrically distributed on both sides, and the center of the dry film gap formed coincides with the projection of the tangent of the outer diameter of the pre-composite roller 12. This allows the brittle dry film on both sides to meet the current collector in a completely symmetrical path and mechanical state, completing a precise initial application. This fundamentally eliminates the risk of film material deviation, stretching, or breakage caused by uneven paths and tension. Neither the dry film unwinding shaft 13 nor the current collector unwinding shaft 11 has a power component. Their power source is the traction force generated by the rotating part of the hot press roller assembly 30 during hot pressing, which pulls the current collector unwinding shaft 11 to unwind. As the dry film unwinding shaft 13 passes through the current collector, it compresses the surface of the current collector, causing the dry film to adhere to the surface of the current collector. At the same time, the dry film unwinding shaft 13 is pulled to rotate by the frictional force of the current collector. Specifically, when the current collector is under tension, it will relatively wrap around and compress the dry film unwinding shaft 13, forming a natural wrap angle. Through the mechanical compression, the dry film is naturally and smoothly transferred or adhered to the surface of the current collector under the combined action of its own weight and the compression force. There is a relative motion tendency between the moving current collector and the stationary surface of the dry film roll, which generates static friction. This friction acts as the power source for driving the dry film unwinding shaft 13 to passively rotate, so that the dry film unwinding shaft 13 releases the dry film at a speed completely synchronized with the speed of the current collector.

[0039] Dry-process membranes are specifically formed by mixing active materials (such as lithium iron phosphate, ternary materials, graphite, etc.), conductive agents (such as carbon black, carbon nanotubes, etc.) and binders (such as polytetrafluoroethylene PTFE, aramid fibers, etc.) in a specific ratio and then directly forming a self-supporting film with a certain mechanical strength through a mechanical pressing process.

[0040] Because dry membrane materials are relatively brittle and have uneven internal stress distribution after pressing, the start-stop impact, speed changes or tension fluctuations during the active driving process can easily induce micro-cracks, powdering or even strip breakage at the edge of the membrane material. However, the dry membrane unwinding shaft 13 has no active power at all, and its unwinding process is completely dragged by the current collector, so that the dry membrane is in an absolutely safe state of zero tension or micro-tension during the entire unwinding and attachment process. For dry membranes with high brittleness and weak cohesion, this is a fundamental guarantee to avoid damage and breakage of their internal structure.

[0041] Two separator film unwinding assemblies 20 are symmetrically arranged. Before entering the final hot-pressing lamination zone (i.e., hot-pressing gap), the separator film led out by them passes through an adsorption plate 40 parallel to its conveying path. The adsorption plate 40 is set so that its surface is completely parallel to the theoretical conveying path of the separator film (which can be set according to the actual conveying path of the separator film). The negative pressure holes 41 opened on it generate uniform adsorption force, which gently and firmly adheres the separator film to the plate surface. This not only completely eliminates the drifting and wrinkling of the separator film during high-speed operation, but also provides it with a stable and flexible... With minimal tension and sufficient adsorption force to support the above operations without causing any impact, all the composite materials are ultimately introduced into the hot pressing gap of the hot pressing roller assembly 30 with relatively high flatness and alignment accuracy, forming a five-layer composite material (isolation film - dry electrode film - current collector film - dry electrode film - isolation film). At this point, since the initial defects have been eliminated to the maximum extent in the previous process, the hot pressing process can be carried out under ideal conditions, and heat and pressure can be applied evenly, thereby efficiently producing a high-quality composite material that is bubble-free, wrinkle-free, and relatively firmly bonded.

[0042] Specifically, the current collector and the dry film have a certain weight and are not easy to float. If the separator film is over-unwound by the separator film unwinding assembly 20, wrinkles will be generated. The current collector, due to the pre-composite roller 12, plays a role in generating corner assistance to lift tension, which can prevent the current collector unwinding shaft 11 from being over-unwound. The negative pressure plate ensures that the separator film can enter the hot pressing gap with relatively high in-plane stability, flatness and precise spatial posture, thus providing ideal pre-process conditions for the hot pressing process, fundamentally avoiding defects such as hot pressing bubbles, local poor composite and uneven composite material thickness caused by separator film floating and wrinkling.

[0043] By unwinding the current collector, the current collector enters the dry film gap after passing through the pre-composite roller 12. The projection of the outer diameter tangent of the pre-composite roller 12 onto the center point of the dry film gap ensures that the dry film achieves a stable and symmetrical stretching path before merging with the current collector. This allows for precise alignment and initial lamination of the current collector, ensuring coating accuracy and consistency on both sides of the current collector and reducing current collector offset and breakage caused by tension differences. Subsequently, the release films led out by the two release film unwinding assemblies 20 pass through their respective adsorption plates 40. The adsorption plates 40 form an active pneumatic constraint guide rail, and the release films are tightly adhered by the adsorption force generated by the negative pressure holes 41. Flattening, specifically, means that the separator film is adsorbed onto the negative pressure plate, which relatively prevents wrinkles and thus achieves a relatively flat state. At the same time, it can also generate a certain tension, which can eliminate the drifting and wrinkling of the separator film during the conveying process, until it is introduced into the hot pressing gap of the hot pressing roller assembly 30. In the hot pressing gap, the dry film and the current collector are hot-pressed and compounded. The negative pressure holes 41 of the adsorption plate 40 can effectively suppress the drifting of the separator film through the negative pressure airflow, ensuring that the surface spacing and flatness are always maintained before entering the hot pressing gap, avoiding bubbles and wrinkles during hot pressing, effectively reducing the defect rate, improving not only the quality and consistency of roller pressing and compounding, but also the stability of roller pressing and compounding operation.

[0044] In this embodiment, as a preferred option, the adsorption plate 40 includes a plate body 42, with one of its surfaces arranged parallel to the conveying path of the corresponding isolation membrane for bonding with the isolation membrane. A negative pressure hole 41 is opened on the surface of the plate body 42 facing the isolation membrane. An adsorption cavity communicating with the negative pressure hole 41 is opened inside the plate body 42. A fan cylinder 45 is connected to the side of the plate body 42 through a pipe, and the input end of the fan cylinder 45 communicates with the adsorption cavity.

[0045] The adsorption chamber is connected to the outside world through the negative pressure hole 41 on the working surface of the plate 42, and is connected to the input end of the fan cylinder 45 through the pipe on the side of the plate 42. When the fan cylinder 45 is running, it can be used as a negative pressure source to continuously draw air from the adsorption chamber through the pipe, thereby forming a stable and uniform negative pressure field in the entire adsorption chamber and all the connected negative pressure holes 41. As a result, the adsorption force is relatively uniformly distributed over a large area of ​​the plate surface, avoiding the situation where the local adsorption force is too strong or too weak. Through the negative pressure hole 41, the plate 42 can evenly and stably adsorb the entire section of the isolation film flowing across its surface onto the plate surface. This not only completely eliminates the drifting and shaking of the film, but also generates a constraint force to help flatten the micro-wrinkles of the isolation film. This provides in-plane stability and relatively flat material for the subsequent hot pressing composite process, avoiding defects such as hot pressing bubbles, wrinkle transmission and uneven composite caused by poor isolation film condition. This significantly improves the finished product quality and consistency of the composite material, as well as the running speed and stability of the roll pressing composite.

[0046] In this embodiment, as a preferred solution, the surface of the plate 42 facing away from the isolation membrane is provided with an air inlet 43 communicating with the adsorption chamber. The inner wall of the adsorption chamber is provided with an air guide 44, one end of which is sleeved outside the negative pressure hole 41. The diameter of the opening at one end of the air guide 44 that covers the negative pressure hole 41 gradually decreases along the extension direction to the diameter of the opening at the other end. A fan 46 is provided inside the fan cylinder 45. When the fan 46 is running, clean air is first drawn in through the air inlet 43 on the back of the plate 42 and the air guide 44 through the negative pressure hole 41. Due to the intake of this airflow, the required negative pressure is directly formed in the adsorption chamber. This negative pressure acts on the isolation membrane through the negative pressure hole 41 to complete its core adsorption and flattening functions. By setting the air guide 44, the air intake of the negative pressure hole 41 can be reduced, which aims to reduce the adsorption force generated by the negative pressure hole 41. At the same time, the air intake of the adsorption chamber is also guaranteed in conjunction with the air inlet 43.

[0047] In this embodiment, as a preferred option, the hot press roller assembly 30 includes a pushing mechanism 32 and two hot press roller mechanisms 31 arranged sequentially along the second direction. The telescopic end of the pushing mechanism 32 is connected to the fixed end of one of the hot press roller mechanisms 31, and is used to push one of the hot press roller mechanisms 31 closer to the other hot press roller mechanism 31 along the second direction. A hot press gap is formed between the two hot press roller mechanisms 31. The rotating ends of the two hot press roller mechanisms 31 rotate towards each other or away from each other, and are used to perform a hot press process on the material in the hot press gap.

[0048] Two hot press roller mechanisms 31 form a pair of controlled rotating rollers through their respective rotating ends. The distance between them is the hot press gap. The telescopic end of the pushing mechanism 32 is connected to the fixed end of one of the hot press roller mechanisms 31. Through linear telescopic movement, the hot press roller mechanism 31 can be fed or retracted slightly in the second direction, thereby adjusting and locking the size and parallelism of the hot press gap between the two rollers. During operation, the rotating ends of the two hot press roller mechanisms 31 can be selected to rotate in opposite directions (the material is pressed in and carried out, and the discharge traction is stable) or in opposite directions. The pushing mechanism 32 provides adjustment of the normal load and the hot press gap distance, and the hot press roller mechanism 31 provides temperature and linear pressure field. The hot press gap can be repeatedly adjusted. With the opposite rotation method, the normal pressing force can be optimized, wrinkles, bubbles and interface slippage can be reduced, and the interface density and bonding strength of the composite material can be improved.

[0049] Furthermore, the extrusion mechanism can be at least one of an electric telescopic rod or a hydraulic rod, both of which are existing technologies and are only cited here for the purpose of achieving the reciprocating movement of the hot press roller mechanism 31 along the second direction through linear telescoping.

[0050] In this embodiment, as a preferred option, the hot press roller mechanism 31 includes a driving member 311 and a composite roller 312 arranged sequentially along a third direction. The output end of the driving member 311 is connected to one end of the composite roller 312 for driving the composite roller 312 to rotate. The fixed end of the driving member 311 and the other end of the composite roller 312 are both fixedly connected to the telescopic end of the pushing mechanism 32.

[0051] The output end (spindle or coupling) of the drive component 311 is rigidly connected to one end of the composite roller 312, directly applying torque to the roller to achieve stable rotation. The drive component 311 can be a drive motor or a stepper motor, which is a known technology. The drive component 311 can also be connected to the composite roller 312 through a reducer. The fixed end of the drive component 311 and the other end of the composite roller 312 are fixed together on the telescopic end of the pushing mechanism 32 (i.e., the same moving base or slide). When the pushing mechanism 32 feeds or retracts to set the hot pressing clearance, the drive component 311 and the composite roller 312 move forward or backward synchronously in a modular form, keeping their relative positions unchanged. This ensures that the composite roller 312 is coaxial, flat, and parallel to the clearance reference. At the same time, both ends are supported by the same telescopic end, effectively reducing the differential displacement and overturning moment of the rotating end or the non-rotating end, so that the roller surface of the composite roller 312 maintains a stable contact line position under heated and pressurized conditions.

[0052] In this embodiment, as a preferred option, the composite roller 312 includes a hot pressing roller body 3121 and a support roller body 3123 extending in a third direction. One end of the hot pressing roller body 3121 is connected to the output end of the drive member 311, and the other end is rotatably connected to the outer surface of the support roller body 3123 through a groove. The end of the support roller body 3123 away from the hot pressing roller body 3121 is connected to the telescopic end of the pushing mechanism 32.

[0053] The composite roller 312 also includes a receiving cavity 3122, a heating cavity 3124, a heating tube 3125, and multiple heat-conducting fins 3126. The receiving cavity 3122 is opened inside the hot press roller body 3121 and is used to contain heat-conducting oil. The heating cavity 3124 is opened inside the support roller body 3123. The heating end of the heating tube 3125 is located inside the heating cavity 3124. Multiple heat-conducting fins 3126 are arranged circumferentially on the inner wall of the heating cavity 3124. The other end of each heat-conducting fin 3126 abuts against the heating end of the heating tube 3125. The end face of the support roller body 3123 is fixedly connected to an air inlet pipe 3127 and an air outlet pipe 3128 that communicate with the heating cavity 3124. The input end of the air inlet pipe 3127 is connected to the output end of the fan cylinder 45.

[0054] By setting up the air inlet pipe 3127 and the air outlet pipe 3128, when the roller pressing and compounding is stopped, the airflow of the fan cylinder 45 can enter the heating chamber 3124 through the air inlet pipe 3127 to dissipate heat on the hot pressing roller body 3121 and the support roller body 3123, avoid continuous high temperature during shutdown, prevent aging of heat transfer oil, thermal fatigue of seals and deformation of hot pressing roller body 3121, and significantly improve the operational reliability and life of the equipment.

[0055] The hot press roller body 3121 is arranged along a third direction. One end of it is rigidly connected to the output end of the drive component 311, directly bearing the torque to achieve stable rotation of the roller surface. The other end of the hot press roller body 3121 is connected to the outer surface of the support roller body 3123 via a grooved rotatable connection, which is equivalent to providing a low-friction support point on the non-drive side to ensure the coaxiality and parallelism of the axis of the hot press roller body 3121. A heating cavity 3124 is formed inside the support roller body 3123, in which the heating tube 3125 is placed, and multiple heat-conducting fins are provided. One end of plate 3126 abuts against heating tube 3125, and the other end abuts against the inner wall of support roller 3123, forming a solid-to-solid heat-conducting structure. A receiving cavity 3122 is provided between support roller 3123 and the outer hot-pressing roller 3121 to hold heat transfer oil. The heat transfer oil in the annular cavity is driven by the rotation of the roller and the temperature difference to form a circumferential or axial composite convection, which evenly transfers the heat from support roller 3123 to the surface of hot-pressing roller 3121 (the outer surface of support roller 3123 and the outer surface of hot-pressing roller 3121 are perpendicular to each other). 21. The inner wall is rotatably connected, i.e., abutting rotation. Lubricating oil can be filled between the outer surface of the support roller 3123 and the inner wall of the hot press roller 3121 (a known method, which can also assist in heat conduction). The end of the support roller 3123 away from the hot press roller 3121 is fixed to the telescopic end of the pushing mechanism 32. The pushing mechanism 32 is responsible for providing the normal load and accurately setting the gap of the hot press clearance. Thus, the drive component 311 is responsible for generating the rotational force, the support roller 3123 is responsible for support and heat transfer, and the heat-conducting fins 31... 26 and the heat-conducting oil are responsible for rapid heat conduction and temperature uniformity, so as to make the temperature distribution of the roller surface of the hot pressing roller 3121 uniform. They work together in space and function. The heating tube 3125, together with the heat-conducting fins 3126, quickly transfers the point heat source to the support roller 3123. The receiving cavity 3122, together with the heat-conducting oil, achieves secondary temperature uniformity, significantly reducing the axial and radial temperature difference and hot spots, reducing the uneven surface temperature of the hot pressing roller 3121. The heat-conducting oil acts as a thermal buffer to reduce the impact of temperature fluctuations on the hot pressing gap and maintain the stability of the roller pressing composite.

[0056] Furthermore, compared to heating the support roller 3123 directly through air via heating tube 3125 instead of through heat-conducting fins 3126 in the heating chamber 3124, the thermal conductivity and convective heat transfer coefficient of air are both relatively low (specifically, the thermal conductivity of air is only about 0.026 W·m). -1 ·K -1 Natural or weakly forced convection typically occurs at 5–30 W·m⁻¹ -2·K -1 This results in high air gap thermal resistance from the heating tube 3125 to the roller wall, easily leading to hot spots and axial temperature differences. However, by using heat-conducting fins 3126 to transfer the point heat source to the support roller 3123 via solid-solid contact (the solid-solid contact thermal resistance is much lower than the air gap), and then using heat-conducting oil to convect within the annular cavity to evenly distribute the heat axially and circumferentially, the heating time is shortened, and the transverse or radial temperature difference and hot spots are reduced. Air has low thermal conductivity and convective heat transfer coefficient, and small heat capacity, easily forming hot spots and temperature differences. When encountering load and linear speed fluctuations, the temperature jaggedness becomes obvious, causing the dry-process brittle film to become locally too soft or too hard, and pores to close, during roller feeding and lamination. Unevenness and edge effects; however, through the heat conduction of the heat-conducting fins 3126, support rollers, heat-conducting oil, and the surface of the hot-pressing roller body 3121, the total thermal resistance from the heating tube 3125 to the roller surface is significantly reduced, resulting in faster heating and more uniform surface temperature (friendly for axial zone control). The large specific heat of the heat-conducting oil can also provide thermal buffering, suppressing temperature fluctuations caused by power and operating condition disturbances. At the same time, the closed-loop circulation of the oil phase can reduce oxidation / contamination in the cavity, reduce the drift of static electricity and dust on thermal boundary conditions, and, in conjunction with the contact between the heat-conducting fins 3126 and the heating tubes 3125, can also avoid local thermal stress concentration, effectively improving composite consistency and reducing defect rate;

[0057] Furthermore, due to the relatively low thermal conductivity of air, heat is unevenly distributed along the roller surface. Air also has a low heat capacity and a long thermal delay. Once the composite material enters the hot-pressing gap, the temperature difference between the surface of the hot-pressing roller 3121 and the material interface will fluctuate, causing localized overheating and melting or insufficient heating of the dry film material surface, leading to defects such as blistering or unclosed pores. However, by using heat-conducting oil in conjunction with heat-conducting fins 3126, the heat from the heating tube 3125 can be rapidly transferred to the supporting roller 3123 via solid conduction. The heat-conducting oil forms a convection circulation within the annular cavity, evenly distributing heat across the entire roller surface. When the composite material passes through the hot-pressing gap, the roller surface can instantly exchange heat stably and uniformly with the dry film and current collector film, effectively promoting the softening of the interfacial binder and pore closure. Simultaneously, it avoids thermal shock and material warping caused by temperature differences. The high specific heat of the heat-conducting oil also provides thermal buffering, allowing the roller to maintain a constant temperature during long-term operation, ensuring a stable temperature and pressure field in the composite zone.

[0058] In this embodiment, as a preferred option, the dry electrode film roll forming composite equipment further includes a winding assembly 50. The winding assembly 50 includes a first winding roller 51, a second winding roller 52, a third winding roller 53, a first guide roller 54, a second guide roller 55, and two heat dissipation pipes 56. The first winding roller 51, the first guide roller 54, the second guide roller 55, and the second winding roller 52 are arranged sequentially along a second direction. The third winding roller 53 is located below the second guide roller 55. The first guide roller 54 and the second guide roller 55 are rotatably connected to the two heat dissipation pipes 56, respectively. One end of the heat dissipation pipe 56 is fixedly connected to a heat dissipation pipe 57. The heat dissipation pipe 57 coincides with the heat dissipation pipe 56 along a first direction. The surface of the heat dissipation pipe 57 is provided with a heat dissipation port facing the composite material.

[0059] Both the first take-up roller 51 and the second take-up roller 52 are equipped with a power source, which can be a stepper motor. The first take-up roller 51 and the second take-up roller 52 are used to wind up the release film on the composite material. The first take-up roller 51 winds up the release film located on one side of the current collector, and the second take-up roller 52 winds up the release film located on the other side of the current collector. The rotational speed of the first take-up roller and the second take-up roller 52 is lower than the rotational speed of the hot-pressing roller body 3121, that is, to ensure that the winding of the release film does not generate a reverse traction force on the hot-pressing gap area. The first guide roller 54 and the second guide roller 55 assist in guiding the peeled release film, making the release film... The angle at which the membrane peels off from the current collector and dry membrane composite structure allows the separator to transition smoothly with a curve rather than detaching sharply, reducing membrane surface stretching, edge tearing, or electrostatic adsorption. The first guide roller 54 and the second guide roller 55 are both mounted on the heat dissipation pipe 56, and together with the heat dissipation vents of the heat dissipation pipe 57, airflow is blown towards the composite material, allowing the separator to be cooled by the airflow simultaneously during the guiding process. This maintains stable tension and a flat shape during the peeling and winding stages. The convective heat dissipation of the airflow blown out through the heat dissipation vents allows the temperature of the composite material to quickly pass through the viscous flow state of the adhesive, promoting its shaping and achieving smooth and damage-free peeling of the separator. At the same time, it avoids the risk of thermal adhesion after winding.

[0060] In this embodiment, as a preferred option, the dry electrode film roll forming composite equipment also includes a body 70, in which a two-position three-way solenoid valve is installed. The two-position three-way solenoid valve is connected in series in the circuit of the drive unit 311. The two-position three-way solenoid valve is provided with a first outlet, a second outlet and an input port. The input port of the two-position three-way solenoid valve is connected to the output end of the fan cylinder 45 through a pipe. The first outlet is connected to the input end of the air inlet pipe 3127 through a pipe. The second outlet is connected to the input end of the heat dissipation pipe 57 through a pipe.

[0061] Furthermore, the two-position three-way solenoid valve is existing known technology, and is only cited here for its purpose of controlling the connection between the output end of the fan cylinder 45 and the air inlet pipe 3127 or the heat dissipation pipe 57. Since the two-position three-way solenoid valve is connected to the circuit of the driving component 311, when the driving component 311 is energized, the circuit of the two-position three-way solenoid valve is synchronously connected and in the first state. When the driving component 311 is de-energized and stops operating, the circuit of the two-position three-way solenoid valve is synchronously disconnected and in the second state. When the two-position three-way solenoid valve is in the first state, the driving component 311 operates, the output end of the fan cylinder 45 is connected to the heat dissipation pipe 57, and the airflow enters the adsorption chamber through the air inlet hole 43 and the negative pressure hole 41, and then enters the heat dissipation pipe 57 after passing through the fan cylinder 45. Subsequently, the airflow is blown out through the heat dissipation vents opened on the two heat dissipation pipes 57, which improves the curing of the dry film in the composite material and facilitates the subsequent peeling of the release liner. When the two-position three-way solenoid valve is in the first state... The output end of the drive component 311 stops rotating, and the output end of the fan tube 45 is connected to the air inlet pipe 3127. The airflow enters the adsorption chamber through the air inlet hole 43 and the negative pressure hole 41, and then enters the air inlet pipe 3127 after passing through the fan tube 45. After entering the heating chamber 3124 through the air inlet pipe 3127, it is discharged through the air outlet pipe 3128 to dissipate heat for the heat transfer oil and heat transfer fins 3126. The airflow is controlled by the drive component 311. When the machine stops, the same air source is redirected to the support roller body 3123 to quickly remove residual heat, suppress heat transfer oil stagnation, thermal fatigue of seals and thermal warping of roller surface, and improve the start-up yield. The unified air source, combined with the automatic distribution of the two-position three-way solenoid valve, makes the air path more compact and the air volume utilization efficiency higher. The airflow can also sweep the cavity dust and reduce static electricity accumulation during circulation, reduce the drift of dust on thermal boundary conditions, and simultaneously improve stability, material heat dissipation efficiency, rapid cooling capability when the machine stops and overall machine reliability.

[0062] More specifically, the current collector unwinding shaft 11 and the pre-composite roller 12 are both rotatably connected to the machine body 70, and are rotated by the traction force generated by the rotation of the current collector through the hot-press roller body 3121. The dry film unwinding shaft 13 is rotatably connected to the machine body 70, and is driven to rotate by the friction force generated when the current collector passes through. At the same time, the machine body 70 is slidably connected to the dry film unwinding shaft 13 by opening a groove extending in the second direction, which is used to adjust the distance between the two dry film unwinding shafts 13. The separator film unwinding assembly 20 can be two separator film unwinding shafts, with separator films sleeved on their surfaces. Both separator film unwinding shafts are rotated by the traction force generated by the rotation of the separator films through the hot-press roller body 3121. The fixed end of the pushing mechanism 32 (i.e., hydraulic rod or electric telescopic rod) is fixedly connected to the machine body 70, specifically including... Two electric telescopic rods are provided. The telescopic end of one electric telescopic rod is fixedly connected to the fixed end of one of the driving components 311. The telescopic end of the other electric telescopic rod is fixedly connected to one end of the support roller 3123 arranged sequentially along the third direction of the corresponding driving component 311. The fixed end of the other driving component 311 is fixedly connected to the machine body 70. One end of the corresponding support roller 3123 is also fixedly connected to the machine body 70. The end of the heat dissipation pipe 56 away from the heat dissipation pipe 57 is fixedly connected to the machine body 70. The first take-up roller 51, the second take-up roller 52 and the third take-up roller 53 in the take-up assembly 50 are all rotatably connected to the machine body 70, and one end of each of them is inserted into the machine body 70. The power source (i.e., stepper motor) of the first take-up roller 51, the second take-up roller 52 and the third take-up roller 53 is correspondingly set in the machine body 70.

[0063] The first direction, the second direction, and the third direction are all straight lines. That is, the first direction refers to a straight line from left to right. Moving to the left and moving to the right are all along the first direction.

[0064] This invention also provides a dry electrode film roll forming method, employing the dry electrode film roll forming equipment described above, comprising:

[0065] A current collector is sleeved on the current collector unwinding shaft. The current collector is unwound through the current collector unwinding shaft and guided to the pre-composite roller. The current collector passes through the dry film gap between the two dry film unwinding shafts under its own weight. The dry film on the dry film unwinding shaft is attached to the current collector to obtain the pre-composite film.

[0066] The pre-composite film passes through a separator film unwinding assembly with a separator film attached. The two separator film unwinding assemblies unwind the separator film so that the two separator films are located on both sides of the pre-composite film. The adsorption plate is attached to the corresponding separator film until the two separator films and the pre-composite film are sent into the hot pressing gap for hot pressing to obtain the composite material.

[0067] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dry electrode film roll forming and laminating equipment, characterized in that: It includes a pre-composite non-powered unwinding assembly, a hot press roller assembly with a hot press gap, and two release film unwinding assemblies; The pre-composite non-powered unwinding assembly includes a current collector unwinding shaft, a pre-composite guide roller, and two dry film unwinding shafts arranged sequentially along the second direction. A dry film gap is formed between the two dry film unwinding shafts. The tangent of the outer diameter of the pre-composite guide roller and the midpoint of the dry film gap along the second direction are arranged sequentially along the first direction and their projections coincide. Two separator film unwinding assemblies are arranged sequentially along the second direction, and their output ends are both located at the output end of the dry film unwinding shaft along the first direction. The two separator film unwinding assemblies are arranged symmetrically about the midpoint of the dry film gap along the second direction along the straight line of the first direction. It also includes two adsorption plates, which are respectively arranged corresponding to two separator film unwinding assemblies and are respectively located between the corresponding separator film unwinding assembly and the hot pressing gap; The hot press roller assembly is used to perform a hot pressing process on the material entering the hot press gap. The adsorption plate includes a plate body, one of the plate surfaces of which is parallel to the conveying path of the corresponding isolation membrane for bonding with the isolation membrane. A negative pressure hole is opened on the surface of the plate body facing the isolation membrane. An adsorption cavity communicating with the negative pressure hole is opened inside the plate body. A fan cylinder is connected to the side of the plate body through a pipe. The input end of the fan cylinder is communicating with the adsorption cavity. The hot press roller assembly consists of two hot press roller mechanisms arranged sequentially along the second direction, and the hot press gap is formed between the two hot press roller mechanisms. The hot press roller mechanism includes a composite roller component. The composite roller includes a hot-pressing roller body, a receiving cavity, a supporting roller body, a heating cavity, a heating tube, and multiple heat-conducting fins extending in a third direction. The receiving cavity is formed in the hot-pressing roller body and is used to contain heat-conducting oil. The heating cavity is formed in the supporting roller body. The heating end of the heating tube is disposed in the heating cavity. The multiple heat-conducting fins are circumferentially arrayed on the inner wall of the heating cavity. The other ends of the multiple heat-conducting fins abut against the heating end of the heating tube. An air inlet pipe and an air outlet pipe communicating with the heating cavity are fixedly connected to the end face of the supporting roller body. The input end of the air inlet pipe is connected to the output end of the fan cylinder.

2. The dry electrode film roll forming equipment according to claim 1, characterized in that: The plate body has an air inlet hole on the surface away from the isolation membrane that communicates with the adsorption chamber. The inner wall of the adsorption chamber is provided with an air guide tube, one end of which covers the negative pressure hole. The diameter of the opening at the end of the air guide tube that covers the negative pressure hole gradually decreases along the extension direction to the diameter of the opening at the other end. A fan is provided inside the fan tube.

3. The dry electrode film roll forming equipment according to claim 1, characterized in that: The hot press roller assembly includes a pushing mechanism, the telescopic end of which is connected to the fixed end of one of the hot press roller mechanisms, for pushing one of the hot press roller mechanisms toward the other hot press roller mechanism in a second direction. The rotating ends of the two hot press roller mechanisms rotate toward each other or toward each other, for performing a hot pressing process on the material within the hot pressing gap.

4. The dry electrode film roll forming equipment according to claim 3, characterized in that: The hot press roller mechanism also includes a drive component arranged sequentially with the composite roller along a third direction. The output end of the drive component is connected to one end of the composite roller and is used to drive the composite roller to rotate. The fixed end of the drive component and the other end of the composite roller are both fixedly connected to the telescopic end of the pushing mechanism.

5. The dry electrode film roll forming equipment according to claim 3, characterized in that: One end of the hot press roller is connected to the output end of the drive component, and the other end is rotatably connected to the outer surface of the support roller through a groove. The end of the support roller away from the hot press roller is connected to the telescopic end of the pushing mechanism.

6. The dry electrode film roll forming equipment according to claim 1, characterized in that: It also includes a winding assembly, which includes a first winding roller, a second winding roller, a third winding roller, a first guide roller, a second guide roller, and two heat dissipation pipes. The first winding roller, the first guide roller, the second guide roller, and the second winding roller are arranged sequentially along a second direction. The third winding roller is located below the second guide roller. The first guide roller and the second guide roller are rotatably connected to the two heat dissipation pipes, respectively. One end of each heat dissipation pipe is fixedly connected to a heat dissipation air pipe. The heat dissipation air pipe coincides with the heat dissipation pipe along a first direction. The surface of the heat dissipation air pipe has a heat dissipation opening facing the composite material.

7. The dry electrode film roll forming equipment according to claim 6, characterized in that: It also includes a body, in which a two-position three-way solenoid valve is installed. The two-position three-way solenoid valve is connected in series in the circuit of the driving component. The two-position three-way solenoid valve is provided with a first outlet, a second outlet and an inlet. The inlet of the two-position three-way solenoid valve is connected to the output end of the fan casing through a pipe. The first outlet is connected to the input end of the air intake pipe through a pipe. The second outlet is connected to the input end of the cooling air pipe through a pipe.

8. A dry electrode film roll forming method, characterized in that: The dry electrode film roll forming equipment as described in any one of claims 1-7 includes: A current collector is sleeved on the current collector unwinding shaft. The current collector is unwound through the current collector unwinding shaft and guided to the pre-composite roller. The current collector passes through the dry film gap between the two dry film unwinding shafts under its own weight. The dry film on the dry film unwinding shaft is attached to the current collector to obtain the pre-composite film. The pre-composite film passes through a separator film unwinding assembly with a separator film attached. The two separator film unwinding assemblies unwind the separator film so that the two separator films are located on both sides of the pre-composite film. The adsorption plate is attached to the corresponding separator film until the two separator films and the pre-composite film are sent into the hot pressing gap for hot pressing to obtain the composite material.

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