Self-adaptive cathode conductive roller
The adaptive cathode conductive roller solves the problem of poor contact between the cathode brush and the fixed roller through the elastically connected shaft and conductive sleeve, realizing stable electroplating of solar cell silicon wafers, reducing contact resistance and mechanical stress risks, and improving electroplating efficiency and quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-23
- Publication Date
- 2026-03-31
AI Technical Summary
In existing technologies, the cathode brush solution suffers from dynamic contact instability, leading to excessive coating thickness. Fixed cathode conductive rollers are prone to causing silicon wafer breakage in thin-film applications, making it difficult to meet the requirements of efficient carrier collection and mechanical stress sensitivity.
An adaptive cathode conductive roller is used, which achieves dynamic and tight contact with the upper surface of the solar cell silicon wafer through the elastic connection between the shaft and the conductive sleeve. This reduces contact resistance, improves current conduction stability, and avoids mechanical stress concentration.
It significantly reduces contact resistance, improves electroplating efficiency and quality, reduces the risk of microcracks and fragmentation in silicon wafers, and achieves stability and cost control in the electroplating process.
Smart Images
Figure CN224062940U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of solar cell electroplating technology, and in particular to an adaptive cathode conductive roller. Background Technology
[0002] In the manufacturing process of crystalline silicon solar cells, the metallization plating of the lower surface is a crucial step in achieving efficient carrier collection. With the development of high-efficiency cell technologies such as PERC and TOPCon, the requirement for the conductivity uniformity of the back grid lines has increased to the ±5μm precision level. Simultaneously, the trend towards thinner wafers (thickness ≤150μm) significantly enhances the mechanical stress sensitivity of contact devices. Current industrial solutions generally employ a plating technique where the cathode contact is plated on the upper surface and the lower surface is plated. However, due to the edge electric field effect, the lower surface plating still requires current conduction through the upper surface cathode. This indirect conduction mode places stringent requirements on the stability of the contact interface. Industry standards require the cathode contact to maintain contact resistance fluctuations of <±5% and a mechanical damage rate of <0.1% during continuous production, posing a dual challenge to the material properties and structural design of the contact devices.
[0003] On the one hand, the existing cathode brush scheme has an inherent defect of dynamic contact instability: the discrete structure of the cathode brush generates large fluctuations, which in turn leads to excessive coating thickness and easily causes the cell fill factor to decay.
[0004] On the other hand, the existing fixed cathode conductive roller solution has a fatal flaw in thin-film applications: when the silicon wafer thickness is ≤150μm, the edge stress generated by the fixed cathode conductive roller can easily exceed the silicon wafer fracture strength, which leads to a surge in microcrack rate and a much higher breakage rate than conventional processes. Furthermore, the geometric mismatch in the contact area further deteriorates the uniformity of current density. Summary of the Invention
[0005] The purpose of this invention is to provide an adaptive cathode conductive roller to solve the problems existing in the prior art.
[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0007] An adaptive cathode conductive roller, comprising:
[0008] The axial portion includes the axial core; and
[0009] The conductive sleeve portion, located outside the shaft portion, includes a shaft ring sleeved on the outer periphery of the shaft and a conductive outer sleeve located outside the shaft ring;
[0010] The conductive outer sleeve is elastically connected to the central ring via an elastic element.
[0011] In one possible implementation, the conductive outer sleeve is a single-layer structure, and the axis is electrically connected to the conductive outer sleeve.
[0012] In one possible implementation, the conductive outer sheath has a multi-layer structure, and the axis is electrically connected to at least the outermost layer of the conductive outer sheath.
[0013] In one possible implementation, the conductive outer sleeve is a single piece or consists of multiple pieces spaced apart axially.
[0014] In one possible implementation, the conductive outer sleeve and the central ring are elastically connected by a plurality of radially distributed cylindrical helical compression springs, the cylindrical helical compression springs being made of stainless steel and having a nickel-plated surface.
[0015] In one possible implementation, the conductive outer sleeve is elastically connected to the central ring via an axially positioned cylindrical helical compression spring.
[0016] In one possible implementation, the conductive outer sleeve and the central ring are elastically connected by a plurality of radially distributed corrugated spring washers.
[0017] In one possible implementation, the conductive outer sleeve is elastically connected to the central ring via a plurality of radially distributed elastic rubber columns.
[0018] In one possible implementation, the conductive outer sleeve is elastically connected to the central ring by a plurality of radially distributed elastic sheets, which are stainless steel elastic sheets or polymer compound elastic sheets.
[0019] In one possible implementation, the conductive outer sleeve is elastically connected to the central ring via a plurality of radially distributed elastic sponges.
[0020] The beneficial effects of the technical solution provided by this utility model include at least the following:
[0021] This technical solution includes a core portion, comprising a shaft; and a conductive sleeve portion located outside the core portion, comprising a core ring sleeved around the outer periphery of the core and a conductive outer sleeve located outside the core ring; wherein the conductive outer sleeve is elastically connected to the core ring via an elastic element. In this configuration, a gravity-adaptive structure achieves dynamic and tight contact between the adaptive cathode conductive roller and the upper surface of the solar cell silicon wafer, significantly reducing the contact resistance between the adaptive cathode conductive roller and the solar cell silicon wafer and improving current conduction stability. This fundamentally solves the problem of uneven coating thickness caused by poor contact in traditional electroplating processes, effectively avoids mechanical stress concentration, significantly reduces the risk of microcracks and fragmentation in solar cell silicon wafers, and achieves a synergistic improvement in electroplating efficiency, quality, and cost control. Attached Figure Description
[0022] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof.
[0023] Figure 1 A radial cross-sectional schematic diagram of an adaptive cathode conductive roller provided in an exemplary embodiment of the present invention is shown.
[0024] Figure 2 This diagram shows an axial cross-sectional view of an adaptive cathode conductive roller provided in an exemplary embodiment of the present invention.
[0025] Figure 3 This diagram illustrates a structural schematic of an adaptive cathode conductive roller according to an exemplary embodiment of the present invention; wherein, Figure 3 (a) is an axonometric view. Figure 3 (b) is a radial cross-sectional view.
[0026] Figure 4 This diagram illustrates a structural schematic of another adaptive cathode conductive roller provided in an exemplary embodiment of the present invention; wherein, Figure 4 (a) is an axonometric view. Figure 4 (b) is a radial cross-sectional view.
[0027] Figure 5 A schematic diagram of another adaptive cathode conductive roller provided by an exemplary embodiment of the present invention is shown.
[0028] Figure 6 A schematic diagram of an axial cross-section of another adaptive cathode conductive roller provided in an exemplary embodiment of the present invention is shown.
[0029] Figure 7 The diagram illustrates the working principle of the adaptive cathode conductive roller provided by this invention.
[0030] In the diagram: 1. Solar cell silicon wafer; 2. Electroplating bath; 3. Support roller; 4. Cathode conductive roller; 41. Shaft; 42. Shaft ring; 43. Conductive outer sleeve; 431. Rigid outer sleeve; 432. Flexible outer sleeve; 44. Elastic element; 5. Anode; 6. Power supply. Detailed Implementation
[0031] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0032] In this specification, identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings of this utility model, while the terms "bottom surface," "top surface," "inner," and "outer" refer to directions towards or away from a specific component, respectively. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more.
[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0034] Example 1
[0035] Figure 1 This diagram shows a radial cross-sectional view of an adaptive cathode conductive roller provided in an exemplary embodiment of the present invention. Figure 2 This diagram illustrates an axial cross-sectional view of an adaptive cathode conductive roller 4 according to an exemplary embodiment of the present invention. The adaptive cathode conductive roller 4 includes a shaft portion and a conductive sleeve portion. The shaft portion includes a shaft 41, and the conductive sleeve portion includes a shaft ring 42 sleeved around the outer periphery of the shaft 41 and a conductive outer sleeve 43 located outside the shaft ring 42. The conductive outer sleeve 43 is elastically connected to the shaft ring 42 via an elastic member 44. The conductive outer sleeve 43 is composed of a single layer of conductive outer sleeve. The shaft 41 is electrically connected to the conductive outer sleeve 43. This single layer of conductive outer sleeve can be a rigid conductive material, such as a stainless steel sleeve, or a non-rigid conductive material, such as a conductive rubber tube.
[0036] In one example Figure 3 This diagram illustrates a structural schematic of an adaptive cathode conductive roller according to an exemplary embodiment of the present invention; wherein, Figure 3 (a) is an axonometric view. Figure 3 (b) is a radial cross-sectional view. In this example, the elastic element 44 is an elastic sheet, which is a stainless steel elastic sheet or a polymer compound elastic sheet.
[0037] In another example, the spindle ring 42 and the conductive outer sleeve 43 are elastically connected by multiple radially evenly distributed cylindrical helical compression springs. These cylindrical helical compression springs are made of stainless steel with a nickel-plated surface. Stainless steel offers good corrosion resistance and strength, and the nickel plating further enhances the spring's corrosion and wear resistance. The wire diameter, number of turns, and spring constant of the cylindrical helical compression springs need to be calculated and selected based on the actual working conditions to ensure they provide appropriate elastic force. For example, the wire diameter is typically between 0.5 and 1.2 mm, the effective number of turns is 5 to 8, and the spring constant is between 0.8 and 1.5 N / mm.
[0038] In another example, the spindle ring 42 and the conductive outer sleeve 43 are elastically connected by multiple radially evenly distributed corrugated spring washers. Corrugated spring washers have unique elastic properties, enabling them to provide large elastic deformation within a small space. Parameters such as waveform height and crest spacing affect their elastic performance. The waveform height is generally between 0.3 and 0.8 mm, and the crest spacing is between 1.2 and 2.0 mm.
[0039] In another example, the spindle ring 42 and the conductive outer sleeve 43 are elastically connected by multiple radially evenly distributed miniature conical disc springs. These miniature conical disc springs have high load-bearing capacity and good elastic stability. Their outer diameter, cone angle, and assembly method need to be optimized according to actual requirements. The outer diameter is generally between 6-10 mm, the cone angle is between 18°-25°, and the assembly method can use 3-5 pieces stacked together.
[0040] In another example, the core ring 42 and the conductive outer sleeve 43 are elastically connected by multiple radially distributed elastic rubber pillars. The Shore hardness of the elastic rubber pillars needs to be selected according to the thickness and characteristics of the solar cell silicon wafer; for thinner solar cell silicon wafers, soft rubber pillars with a Shore hardness between 50-60 HA can be selected; for thicker solar cell silicon wafers, hard rubber pillars with a Shore hardness between 70-80 HA can be selected. Simultaneously, the dynamic compression set of the elastic rubber pillars should be less than 10% to ensure their long-term stability.
[0041] In another example, the spindle ring 42 and the conductive outer sleeve 43 are elastically connected by multiple radially evenly distributed elastic sponges. The elastic sponges are usually made of polyurethane or silicone-based materials that are resistant to aging and have excellent insulation properties. Their porous structure can provide cushioning and shock absorption performance, effectively reducing the impact of mechanical vibration on the conductive components.
[0042] In this embodiment, a servo motor is selected to drive the shaft, which can precisely control the rotational speed of the shaft and can be flexibly adjusted according to different stages of the electroplating process.
[0043] In this embodiment, the gravity applied by the adaptive cathode conductive roller to the solar cell silicon wafer is determined by the number of elastic elements, the specifications of the elastic elements, the wall thickness of the conductive outer sleeve, and the material of the conductive outer sleeve.
[0044] Optionally, the cross-sectional shape of the axis 41 includes, but is not limited to, one of the following: circle, ellipse, triangle, quadrilateral, pentagon, hexagon, and octagon.
[0045] Optionally, the shaft 41 may be composed of a single material or more than one material. For example, an insulating material or a conductive material may be coated on the outside of the shaft 41.
[0046] Optionally, the cross-sectional shape of the central ring 42 includes, but is not limited to, one of the following: circular, elliptical, triangular, quadrilateral, pentagonal, hexagonal, or octagonal.
[0047] Example 2
[0048] This embodiment is basically the same as Embodiment 1, except that:
[0049] Figure 4 This diagram illustrates a structural schematic of another adaptive cathode conductive roller provided in an exemplary embodiment of the present invention; wherein, Figure 4 (a) is an axonometric view. Figure 4 (b) is a radial cross-sectional view. In this embodiment, the conductive outer sleeve 43 consists of a rigid outer sleeve 431 and a flexible outer sleeve 432. The flexible outer sleeve 432 is electrically connected to the shaft 41. Depending on the specific application requirements, the conductive outer sleeve 43 can be composed of two or more conductive outer sleeves. The shaft 41 is electrically connected to at least the outermost layer of the conductive outer sleeve 43. The shaft 41 can be electrically connected to any layer of the conductive outer sleeve 43, or to all layers of the conductive outer sleeve 43, but it must be electrically connected to the outermost layer of the conductive outer sleeve 43.
[0050] Example 3
[0051] This embodiment is basically the same as Embodiment 1, except that:
[0052] Figure 5 The diagram shows a structural schematic of another adaptive cathode conductive roller provided by an exemplary embodiment of the present invention. In this embodiment, the elastic element 44 is an axially arranged cylindrical helical compression spring. The spring connects the conductive outer sleeve 43 and the shaft ring 42. The spring is a stainless steel spring or a polymer compound spring.
[0053] Example 4
[0054] This embodiment is basically the same as Embodiment 1, except that:
[0055] Figure 6 The diagram shows an axial cross-sectional view of another adaptive cathode conductive roller provided by an exemplary embodiment of the present invention. In this embodiment, the adaptive cathode conductive roller 4 is implemented as a shaft part corresponding to multiple conductive sleeve parts. Multiple conductive outer sleeves 43 are provided on the outer periphery of the shaft 41 at intervals. The inner ends of each conductive outer sleeve 43 are connected to a shaft ring 42 by an elastic member 44. The shaft ring 42 is sleeved on the shaft 41.
[0056] Next, combined Figure 7 The working principle of the adaptive cathode conductive roller involved in the embodiments of this utility model is explained.
[0057] Step 1: After the solar cell silicon wafer 1 comes into contact with the supporting roller 3, it moves horizontally.
[0058] Step 2: After the solar cell silicon wafer 1 moves into the electroplating solution tank 2, the lower surface of the solar cell silicon wafer 1 contacts the electroplating solution in the electroplating solution tank 2, and the upper surface of the solar cell silicon wafer 1 contacts the adaptive cathode conductive roller 4 set above the electroplating solution tank 2; wherein, the conductive sleeve of the adaptive cathode conductive roller 4 dynamically and tightly adheres to the upper surface of the solar cell silicon wafer 1 by its own weight.
[0059] It is worth mentioning that the supporting roller and the adaptive cathode conductive roller rotate synchronously, and the difference in their linear speeds does not exceed ±0.1 m / min. To achieve this precise synchronous rotation, a servo motor can be used in conjunction with an absolute encoder, and the synchronous control of the supporting roller and the adaptive cathode conductive roller can be achieved via a CAN bus.
[0060] Step 3: Connect the adaptive cathode conductive roller 4 to the negative terminal of the power supply 6, and connect the anode 5 in the electroplating bath 2 to the positive terminal of the power supply 6. After turning on the power supply 6, electroplating will occur on the lower surface of the solar cell silicon wafer 1.
[0061] It is understandable that the self-weight design of the conductive sleeve in the adaptive cathode conductive roller needs to be precisely calculated based on the size, thickness and electroplating process requirements of the solar cell silicon wafer to ensure that it can provide sufficient pressure for good electrical contact without putting too much pressure on the solar cell silicon wafer and causing damage. This enables the adaptive cathode conductive roller to adaptively adjust according to the slight undulations on the surface of the solar cell silicon wafer during the bonding process, ensuring the uniformity of contact across the entire upper surface.
[0062] It should be noted that in the above embodiments, the power is transmitted to the conductive outer sleeve through the shaft.
[0063] This technical solution includes a core portion, comprising a shaft; and a conductive sleeve portion located outside the core portion, comprising a core ring sleeved around the outer periphery of the core and a conductive outer sleeve located outside the core ring; wherein the conductive outer sleeve is elastically connected to the core ring via an elastic element. In this configuration, a gravity-adaptive structure achieves dynamic and tight contact between the adaptive cathode conductive roller and the upper surface of the solar cell silicon wafer, significantly reducing the contact resistance between the adaptive cathode conductive roller and the solar cell silicon wafer and improving current conduction stability. This fundamentally solves the problem of uneven coating thickness caused by poor contact in traditional electroplating processes, effectively avoids mechanical stress concentration, significantly reduces the risk of microcracks and fragmentation in solar cell silicon wafers, and achieves a synergistic improvement in electroplating efficiency, quality, and cost control.
[0064] In the embodiments disclosed in this utility model, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments disclosed in this utility model according to the specific circumstances.
[0065] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.
Claims
1. A self-adapting cathode conductive roller, characterized in that, The utility model relates to a kind of electrically conductive sleeve pipe and shaft ring elastic connection structure, including: Shaft core, it includes shaft core;And Electrically conductive sleeve pipe portion, it is located in the outside of the shaft core portion, it includes the shaft core ring that is sleeved to the shaft core periphery and the electrically conductive outer sleeve pipe that is located in the outside of the shaft core ring; Wherein, the electrically conductive outer sleeve pipe is elastically connected with the shaft core ring by elastic member.
2. The self-adapting cathode conductive roller according to claim 1, wherein, The electrically conductive outer sleeve pipe is single-layer structure, and the shaft core is electrically connected with the electrically conductive outer sleeve pipe.
3. The self-adapting cathode conductive roller according to claim 1, wherein, The electrically conductive outer sleeve pipe is multilayer structure, and the shaft core is electrically connected with at least the outermost layer of the electrically conductive outer sleeve pipe.
4. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe is a whole, or it is composed of multiple roots that are axially spaced.
5. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe and the shaft core ring are elastically connected by multiple radially distributed cylindrical spiral compression springs, and the material of the cylindrical spiral compression spring is stainless steel, and the surface is treated by nickel plating.
6. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe and the shaft core ring are elastically connected by an axially arranged cylindrical spiral compression spring.
7. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe and the shaft core ring are elastically connected by multiple radially distributed wave-shaped spring washers.
8. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe and the shaft core ring are elastically connected by multiple radially distributed elastic rubber columns.
9. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe and the shaft core ring are elastically connected by multiple radially distributed elastic sheets, and the elastic sheet is stainless steel elastic sheet or high polymer compound elastic sheet.
10. The self-adapting cathode conductive roller of claim 1, wherein, The electrically conductive outer sleeve pipe and the shaft core ring are elastically connected by multiple radially distributed elastic sponges.