Laser-Assisted Soldering Techniques for Solar Cell Manufacturing

Photovoltaic module with improved soldering reliability through optimized laser welding. The module features a junction box with a plate that is precisely positioned to create a specific width ratio between the soldering seam in the first region and the direct weld in the second region. This deliberate width variation enables the laser welder to achieve optimal soldering performance while maintaining reliability. The module's design ensures that the soldering seam in the first region is narrower than the weld in the second region, preventing desoldering due to thermal shock.

Source

A low-temperature photovoltaic solder alloy for series welding of PERC, TOPcon, and HJT solar cells. The solder alloy combines a low melting point with high strength, enabling reliable welding of solar cells with thinned silicon wafers. The alloy composition includes Sb, Ni, Ge, In, and Co elements that enhance tensile strength and peeling force through solid solution strengthening and dispersion strengthening. The solder alloy is produced through a hot-dip coating process on copper substrates, providing a simple and cost-effective solution for series welding applications.

Source

Laser exposure solar cell welding device and photovoltaic module processing equipment that enables stable heat generation through a novel laser-based welding system. The device employs a laser system to provide controlled heat input during solar cell welding, eliminating the need for traditional welding lamps with filaments. This laser-based approach enables improved welding quality, reduced thermal management requirements, and lower equipment costs compared to conventional systems.

Source

A method for string welding interdigitated back contact (IBC) solar cells without using solder paste. The method employs a laser-based process that directly welds the solar cells together through their finger-like contacts, eliminating the need for solder paste. The laser welds the contacts together while maintaining the structural integrity of the solar cells, achieving efficient string welding of IBC solar cells without the environmental and operational drawbacks associated with traditional soldering methods.

Source

Low-temperature lead-free solder for photovoltaic cells that eliminates thermal expansion issues while maintaining environmental sustainability. The solder has a low melting point and coefficient of thermal expansion, enabling precise assembly of ultra-thin photovoltaic cells. The solder is prepared through a novel coating process that enhances its performance characteristics while maintaining environmental compliance.

Source

A welding method for photovoltaic cells and modules that enables reliable and efficient interconnection through solder joints. The method involves creating a solder layer on the cell substrate at a specific pad location, then lapping solder strips from adjacent cells to achieve precise contact. This approach enables precise soldering of adjacent cells while maintaining the required welding tension and minimizing solder wetting issues. The soldering process is performed through a controlled lapping sequence that ensures precise solder alignment and coverage, resulting in reliable electrical connections.

Source

Automated laser soldering system that enables precise and efficient welding of complex components by dynamically adjusting laser parameters based on the specific welding requirements. The system employs real-time monitoring of the welding process, including temperature and energy output, to automatically select optimal spot size and type for each weld joint. This enables precise control over solder placement, temperature management, and energy distribution, resulting in improved weld quality and reduced defects.

Source

A method to improve the quality and efficiency of soldering in photovoltaic modules without main grids. The method involves rolling the low-temperature solder strip with flux inside to release and attach flux to the strip surface. This pretreated strip is used to connect the photovoltaic cells instead of plain flux-containing strip. Rolling the strip before soldering increases tin wetting, flux migration, and oxide removal for better solder joints. The flux-coated strip also prevents brittleness issues.

Source

A method for rapid laser soldering of materials using laser beams. The method employs a laser, a holder, a beam-guiding device, and a beam-focusing device to selectively solder specific areas of a material. The laser beam is directed through a beam-guiding device to precisely focus the laser energy onto the desired areas, while the beam-focusing device maintains optimal beam intensity and wavelength. This enables efficient laser soldering of specific regions of a material, eliminating the need for liquid soldering.

Source

A low-temperature solder alloy for photovoltaic applications that enables reliable stringing of solar cells through reduced welding temperatures. The alloy, comprising tin-lead-tin ternary alloy with indium addition, achieves a melting point of approximately 130°C, significantly lower than conventional tin-lead solder. The alloy's refined grain structure and improved grain boundary refinement properties enable enhanced bonding strength between the solder and the solar cell substrate, while maintaining sufficient wettability for efficient stringing.

Source

A method for laser beam soldering that enables high-quality connections while minimizing surface defects. The process employs a laser beam with two distinct focal planes: a large-area beam for the soldering area and a smaller-area beam for the seam root. This dual-beam configuration ensures direct heat transfer from the laser beam to the seam root, reducing edge notches and spatter compared to conventional single-beam systems. The smaller-area beam is positioned within the larger area beam, allowing precise control over the soldering process while maintaining optimal laser energy distribution.

Source

A low-temperature photovoltaic solder for high-efficiency solar cells that enables reliable connections at temperatures below 150°C. The solder comprises a combination of Sn, Bi, In, Zn, P alloy powder, graphene, thermosetting resin, curing agent, and organic acid. The alloy powder is prepared through atomization with precise composition and particle size control, while the thermosetting resin provides mechanical strength and thermal stability. The solder achieves high wetting properties and tensile strength while maintaining low oxidation resistance, making it suitable for photovoltaic module assembly at lower temperatures compared to traditional solders.

Source

A laser welding device that eliminates the complex and expensive tin ball feeding mechanism while maintaining high reliability. The device features a carrier tape with embedded solder inlays, where the solder is arranged in a sheet-like structure. The tape is conveyed by a carrier belt system, which transports the solder to the laser head. The laser melts and vaporizes the solder and tin, creating a molten jet that is directed to the welding area through a high-pressure gas system. This eliminates the need for individual tin ball feeding mechanisms, reducing production complexity and cost.

Source

Laser welding method and soldering machine that eliminates the traditional laser welding process's limitations by employing a novel laser welding technique that uses a high-temperature soldering process to create a permanent bond. The laser welding method involves melting the solder through a controlled laser energy density, rather than traditional molten soldering. This approach enables precise control over the soldering process, eliminating the structural damage typically associated with traditional laser welding. The soldering machine incorporates this laser welding method to create permanent solder joints, eliminating the need for flux and reducing environmental impact.

Source

A method and device for efficient solar cell welding that eliminates the need for manual positioning and double welding. The method employs a laser system that simultaneously heats multiple welding groups in a single pass, with each group's points aligned using a precision camera system. The laser's focused beam is directed through a beam expander and focusing lens to create precise spots that accurately target the welding points. This single-pass approach eliminates the need for manual positioning and double welding, significantly improving welding efficiency compared to conventional methods.

Source

A molten solder for photovoltaic modules that enables efficient bonding between electrode wires and semiconductor substrates. The solder composition combines tin (Sn) with indium (In) and lead (Pb) in a specific ratio, with a melting point between 181°C and 183°C, to achieve high bonding strength while minimizing thermal stress. The solder layer forms a strong bond with the electrode wire's conductive core, enabling reliable electrical connections between the wire and the semiconductor substrate.

Source

A method for welding heterojunction solar cells that improves yield and efficiency compared to existing methods. The method involves printing a thin layer of material on the welding points of the solar cells before welding. This adhesion layer helps bridge between the cells and the welding strip during welding, improving the connection and pull force. It allows welding at lower temperatures to avoid cell damage. The printed layer is made of a material like silver that melts earlier than the cell material. When the welding strip fuses with the cell, the printed layer connects them.

Source

A welding device for photovoltaic cells that enhances welding tension by optimizing soldering conditions. The device employs a controlled molten soldering process that prevents rapid solidification during the welding process. The molten solder is maintained at a stable temperature, allowing it to solidify slowly and evenly between the photovoltaic cell and the electrode. This controlled solidification prevents the formation of localized solder droplets that can compromise the welding process. The device enables stable and consistent soldering conditions, resulting in improved welding tension and overall cell performance.

Source

Laser beam soldering method for joining coated components with improved wetting and mechanical properties. The method employs a laser beam with a diameter ratio of at least 2.5 between the beam diameter and the filler material diameter, ensuring sufficient heating area for effective wetting and filling of the coating. This ratio enables the laser beam to penetrate the coating thickness and fill the gap between the components, resulting in improved connection quality compared to conventional laser brazing.

Source

A non-contact laser soldering machine that eliminates component displacement during the soldering process by using a laser-aided soldering system. The machine employs a laser beam to selectively melt and join electronic components, eliminating the need for physical contact between the soldering tip and the component. The laser beam precisely targets the soldering points, forming a strong bond without physical contact. This non-contact soldering approach enables precise placement of components during assembly, reducing displacement and improving assembly reliability.

Source

A welding process method and equipment for soldering that eliminates defects in traditional liquid soldering processes. The method employs a laser to selectively melt the solder paste layer during the welding process, maintaining its thickness while ensuring reliable soldering. This approach enables precise control over soldering conditions and eliminates the need for multiple soldering steps or specialized equipment. The laser-based soldering method enables efficient and reliable soldering of complex assemblies while maintaining consistent solder thickness throughout the process.

Source

A lead-free solder strip for solar photovoltaic cells that enhances soldering performance and reliability through its unique composition. The solder strip comprises Sn-Bi alloy with an added layer of I2, which significantly improves solder wetting properties and reduces brittleness compared to traditional Sn-Pb solder. The I2 layer also enhances the solder's ability to form strong, full-flow joints in solar cells. The composition is achieved by combining Sn-Bi with I2 in a calculated weight ratio, with the added layer applied from the inside of the strip to the surface. This composition provides superior soldering performance, reliability, and durability for solar photovoltaic applications.

Source

A method for welding solar cells and photovoltaic modules that improves efficiency by optimizing soldering parameters. The method employs a specialized soldering process that selectively melts the tin layer on the solar cell side, creating a direct contact between the copper grid lines and the battery sheet. This approach eliminates the conventional copper-tin soldering limitations, enabling higher-quality welds with improved electrical conductivity. The method also addresses the environmental and manufacturing challenges associated with traditional soldering processes by minimizing waste and reducing the need for high-cost tin plating.

Source

A method for welding flexible printed circuit board (FPCB) ribbons that enables soldering solar cells through a novel approach. The method involves cutting the FPCB into thin, uniform strips and then applying solder to the strip edges. This enables the formation of solder joints along the entire length of the FPCB, eliminating the traditional ribbon welding limitations. The FPCB strips can be cut to precise widths and lengths, allowing for precise control over the soldering process. The method provides a flexible and efficient way to solder solar cells while maintaining the FPCB's inherent flexibility and durability.

Source

A welding device and robot system that enables precise laser soldering of electronic components while maintaining reliable performance. The device features a laser beam that selectively supplies solder to specific areas of the workpiece, with the solder flow controlled by a dedicated storage chamber. The robot system enables precise positioning of the welding device, allowing it to be tilted to optimize solder delivery while maintaining laser beam alignment. This integrated approach eliminates the need for manual soldering positions and eliminates the thermal damage associated with traditional laser soldering methods.

Source

Photovoltaic ribbon for solar cells that enables low-temperature welding while maintaining high repair rates and efficiency. The ribbon comprises a conductive base tape with a specially formulated solder layer containing tin, lead, and bismuth. The solder composition is optimized to achieve a melting point of approximately 180°C, enabling reliable welding at temperatures below the conventional Sn-Pb alloy melting point. The solder layer distributes uniformly across the base tape surface, ensuring excellent solderability and preventing warpage. This innovative composition enables precise control over the soldering process while maintaining the critical properties required for solar cell assembly.

Source

A laser soldering system that enables simultaneous soldering of conductors and resistors using different wavelengths. The system employs two laser beams with distinct wavelengths, one for the conductor and one for the resistor, which are delivered through a single irradiation port. The system achieves high-quality soldering by preheating the resistor with a shorter wavelength laser beam, followed by melting the conductor with a longer wavelength laser beam. This dual-wavelength approach enables efficient soldering while minimizing substrate damage from reflected laser light.

Source

Solder ball laser welding method that improves the reliability and quality of soldering by controlling laser power density during the soldering process. The method employs a laser welding system with adjustable laser power density control, enabling precise control over the soldering process. The laser power density is dynamically adjusted based on the solder ball's position relative to the laser beam, preventing sudden changes in power that can cause solder ball splashing and pad damage. The system also monitors and controls the molten solder ball's movement to prevent bubbles during cooling and solidification. This controlled laser power density and molten solder ball movement enable consistent and reliable soldering results.

Source

A laser welding system for solar cell bus bars that enables high-quality, efficient, and precise bus bar welding through the use of a laser welding process. The system employs a pulsed laser with advanced wavelength tuning capabilities to precisely control the welding parameters, enabling precise control over the welding process. The laser welding process eliminates the need for manual soldering techniques and traditional fluxes, while maintaining high-quality welds with reduced material residues and oxidation. The system features an electronically controlled motion platform that enables precise movement of the laser head along the bus bar, allowing for complete strip coverage.

Source

A method for forming a package that eliminates thermal stress during reflow soldering by using a multiple laser reflow process. The method involves first irradiating a portion of the top surface of the package component with laser light to melt solder joints between components, followed by a second laser light irradiation that solidifies the solder joints. This sequential laser reflow process enables simultaneous soldering of multiple solder joints while maintaining the structural integrity of the package.

Source

A solar cell bus bar welding device that enables precise and uniform laser welding of photovoltaic modules. The device features a non-metallic welding platform with integrated laser and sensor components, a laser adjustment mechanism that connects to the laser, and a laser beam that is positioned above the welding platform. The laser beam is precisely controlled by the adjustment mechanism to achieve optimal welding conditions, including temperature uniformity and positional accuracy. This eliminates the traditional limitations of manual soldering and resistance heating welding, ensuring consistent and reliable bus bar connections.

Source

A solar cell module junction box welding device that improves welding uniformity and speed through precise laser welding. The device features a dedicated welding platform for mounting the solar cell module, a laser welding mechanism specifically designed for the junction box, and a control system that coordinates the laser beam with the welding process. The laser welds the second end of the connecting wire to the solder joint in the junction box, eliminating the need for manual bending and heat application. The system ensures consistent weld quality while significantly enhancing production efficiency compared to traditional soldering methods.

Source

Lead-free solder alloy for photovoltaic welding strips that provides improved brazing performance and reliability compared to traditional lead-based alloys. The alloy combines tin and bismuth to achieve a low melting point of 139°C, enabling efficient brazing of photovoltaic cells while maintaining high strength and thermal stability. The alloy's unique composition enables effective wetting of the copper substrate, forming a strong intermetallic bond during brazing. This leads to improved solder joint strength and thermal resistance, particularly during high-temperature welding processes. The alloy's low melting point also enables the use of conventional brazing techniques, eliminating the need for specialized equipment.

Source

A low-temperature photovoltaic ribbon for solar cells that enables high-efficiency welding at temperatures below 200°C. The ribbon's unique composition and preparation method achieve improved welding performance through reduced soldering temperatures, while maintaining the necessary mechanical integrity for cell integrity. This approach addresses the common issues of high fragmentation rates and reduced welding strength associated with conventional photovoltaic ribbons.

Source

A solar cell bus bar welding device that eliminates the precision issues of traditional manual soldering and resistance heating welding. The device employs laser welding instead of traditional methods, allowing precise control over the welding process while eliminating positional deviations between the bus bar and drainage bar. The device features a laser welding system, precision temperature and pressure sensors, and a moving mechanism that enables customized welding paths.

Source

Self-flowing soldering method and system for laser welding that enables efficient and high-quality laser welding of solder joints by converting solid-phase tin into liquid-phase tin for storage and continuous flow onto the workpiece. The method involves electrically heating the solid tin to a liquid state, storing it in a liquid phase, and then using the laser to heat the liquid phase solder to achieve complete penetration. This approach eliminates the need for fluxes, manual soldering, and the associated issues of solder paste collapse and bubble formation during reflow. The liquid-phase solder flows continuously onto the workpiece, ensuring consistent quality and production efficiency.

Source

A solar cell solder that enables reliable and high-temperature soldering of solar cells. The solder comprises a solder alloy with a specific composition that provides optimal thermal conductivity and mechanical properties for high-temperature soldering applications. The solder alloy is formulated to achieve a balance between thermal conductivity, electrical conductivity, and mechanical strength, enabling reliable soldering of solar cells at elevated temperatures.

Source

Laser soldering jig and method for precise, high-temperature soldering of small components. The jig features a heat-conductive portion integrated into the design, where the laser beam is concentrated to heat the soldering area. This concentrated heat transfer enables precise melting of the solder material without direct laser irradiation of the surrounding components, resulting in improved weld quality and reduced thermal damage. The jig's heat-conductive material ensures efficient heat transfer while maintaining structural integrity.

Source

A method for joining electronic components through laser-assisted soldering that eliminates the need for a soldering iron. The method involves creating a controlled opening in the component's surface using a laser beam, followed by direct laser heating of the solder layer through the opening. This approach enables high-temperature soldering without the need for a heat source, as the laser beam directly interacts with the solder layer through the opening. The laser beam penetrates the component's surface and selectively targets the solder layer, allowing precise control over the soldering process. This method achieves high-quality solder joints with reduced thermal input compared to traditional soldering techniques.

Source

A low-temperature alloy solder for photovoltaic cell welding that achieves improved electrical conductivity, tensile strength, and oxidation resistance. The solder composition is optimized to meet the requirements of solar cell welding without traditional lead-tin solder, enabling reliable ohmic contact between battery components and copper wires. The solder composition balances electrical conductivity, mechanical properties, and thermal stability, making it suitable for both traditional and solderless welding processes in solar cell manufacturing.

Source

Laser soldering method for connecting crystalline silicon solar cells through conductive strips. The method enables precise contact between the conductive soldering strip and the solar cell electrodes by creating a uniform vacuum environment between the press plates. This enables the soldering strip to achieve tight contact with the solar cells, eliminating the thermal expansion mismatch issues typically encountered in conventional soldering techniques. The method can be applied for series, parallel, or series-parallel connections in crystalline silicon solar cell modules.

Source

A specialized welding tip for single-crystalline silicon solar cells that eliminates solder overflow and cell damage during soldering. The tip features a unique design that incorporates a built-in solder removal mechanism, allowing excess solder to be efficiently discharged without compromising the solar cell surface. This eliminates the traditional tin-overlap phenomenon that occurs when solder flows onto the solar cell surface during soldering, preventing rework and damage to the cells.

Source

Solar cell electrode made with active solder and its manufacturing method, which enables precise electrode formation through lower-temperature soldering. The method employs a specialized solder alloy with controlled rare earth content, which melts at temperatures below 450°C. The solder is applied to the solar cell substrate, and upon cooling, it forms a conductive pattern on the substrate's surface. This approach eliminates the need for high-temperature sintering and simplifies electrode formation, while maintaining the desired electrical properties. The solder can be selectively plated to enhance durability and electrical conductivity.

Source

A photovoltaic module crystalline silicon cell welding process that improves the efficiency and reliability of solar cell assembly by eliminating the need for manual soldering. The process employs a high-temperature laser welding system that precisely joins the cell and solder ribbon without the need for manual soldering irons or stringers. The laser welding system enables the assembly of multiple cells in a single pass, eliminating the traditional welding process bottleneck of decreasing strip spacing and increasing strip count. The laser welding system also eliminates the need for tinned soldering tapes and traditional soldering techniques, reducing material waste and improving cell reliability.

Source

A laser soldering process that enables high-speed soldering of soft solder joints using a green laser beam. The process employs a green laser with a wavelength of 532 nm, which is specifically designed to enhance soldering performance by reducing reflection and absorption. The green laser beam is used to heat the solder, achieving soldering speeds comparable to traditional soldering methods while maintaining the benefits of soft solder joints.

Source

A laser soldering method for photovoltaic modules that enables precise, reliable, and efficient soldering of solar cells in series connection. The method employs a specialized soldering process that utilizes a precisely controlled laser beam profile to precisely melt the soldering material through a narrow gap between the solar cells. The gap is maintained constant throughout the soldering process, ensuring uniform soldering quality. This approach eliminates the conventional issues of contact failure and degradation associated with traditional soldering methods. The soldering process is performed using a laser soldering machine, with the laser beam precisely controlled to focus on the molten soldering material. The soldering process is particularly effective for solar cells with narrow gap sizes, enabling precise soldering of the solar cells in series connection.

Source

Soldering material for joining copper-based components, particularly in solar cell applications, that enhances bond reliability through a novel surface treatment layer. The material comprises a copper-based substrate with a surface treatment layer containing an amorphous layer with oxygen atoms having a higher affinity than copper. This layer forms a barrier against oxidation and diffusion of copper and oxygen, ensuring improved wetting and bond integrity. The treatment layer thickness is defined at 8 nm or more, with a maximum thickness of 300 nm. The material is applied as a soldering joint to copper-based components, particularly in solar cell modules where high-temperature soldering conditions are encountered.

Source

A lead-free tin-silver alloy plating layer composition for soldering applications, particularly in solar cells, that significantly improves electrical conductivity while maintaining cost-effectiveness. The composition comprises 16-40% zinc, 0.1-1% silver, 0.01-0.3% aluminum, 0.001-0.01% phosphorus, 0.001-0.5% bismuth, and the balance tin. This composition enables excellent solderability and conductivity while reducing manufacturing costs compared to traditional lead-based soldering systems.

Source