#China #Risen Energy #Ningbo #HJT Technology #Ultra-Thin Wafers

Risen Energy's Journey to Ultra-Thin Silicon Wafers

As discussions about space-based photovoltaics gain momentum within the industry, Risen Energy stands out as a pioneer by emphasizing the importance of lightweight and high-efficiency solar panels. The transition from concept to mass production in ultra-thin silicon wafers marks a significant milestone in photovoltaic technology. Through revolutionary Heterojunction Technology (HJT), Risen Energy is poised to lead the charge in sustainable energy solutions.

The Need for Ultra-Thin Silicon Wafers

Understanding the drive towards thin wafers is crucial. In solar panel production, silicon wafers account for approximately 55% of the manufacturing cost of HJT cells. Consequently, reducing wafer thickness is one of the most direct and effective methods to lower overall production costs. Beyond economics, this approach aligns closely with the intrinsic nature of HJT technology. The process operates at low temperatures, below 200°C, allowing for a gentler handling of silicon wafers. This significantly mitigates the risks of warping and breakage typically associated with high-temperature processes used in traditional methods such as PERC and TOPCon.

Maintaining Reliability Despite Reduced Thickness

One of the core challenges of developing ultra-thin wafers is ensuring their mechanical integrity and reliability. Risen Energy has conducted extensive research and practical trials to optimize efficiency, yield, and mechanical strength.

Efficiency Compromises

Experimentation revealed an intriguing phenomenon known as the “swing effect.” As wafer thickness decreases, short-circuit current density (Jsc) dips while open-circuit voltage (Voc) rises, with fill factor (FF) remaining stable. Risen Energy's HJT Hyper-ion panels, made from 110µm thick wafers, have reached an average efficiency of 26.4%, with some batches exceeding 26.6%. This shows that reducing wafer thickness does not necessarily limit performance.

Optimizing Manufacturing Process

A complete redesign of wafer cassette configurations from horizontal to vertical loading, alongside the refinement of automation and transport processes, has resulted in a stable product yield of over 99.5% with wafer damage levels below 0.25%. These advancements affirm that the manufacturing complexities associated with thinner wafers can be successfully addressed through systemic innovation in technologies and processes.

Understanding Mechanical Strength

Comparative tests demonstrated that PERC elements at 150µm and TOPCon at 130µm failed during bending tests, while wafers below 100µm exhibited remarkable flexibility. This exceptional flexibility of HJT elements opens opportunities for lightweight module designs that can meet unique deployment conditions.

Exploring Aerospace Applications

Risen Energy's HJT Hyper-ion products for terrestrial solar power installations utilize wafers that are 110µm thick, culminating in an element thickness around 95µm. This thickness strikes an optimal balance between efficiency, production yield, and reliability while notably reducing costs. However, there's a broader horizon. In aerospace applications, where maximum power-to-weight ratio is critical, solar cells may need to be as thin as 70µm or less. Risen Energy’s sustained commitment enables the production of elements thinner than 70µm.

Innovations for Ultra-Thin Element Performance

Conventional high-temperature soldering processes are unsuitable for ultra-thin elements. To tackle this, Risen Energy has pioneered the Hyper-link technology, an un-stressful interconnection method protected by over 50 patents, preventing thermal stress during soldering. This innovation is reinforced by rigorous reliability testing exceeding IEC standards, demonstrating how Hyper-ion modules with ultra-thin wafers maintain superior performance characteristics over traditional systems.

Integrated Research and Development

Reflecting on Risen Energy’s pathway with ultra-thin wafers reveals that success is grounded not only in individual breakthroughs but in collaborative innovations linking wafer technologies, low-silver metallization, zero-busbar elements, and Hyper-link connections into a cohesive engineering framework. This approach establishes a comprehensive competitive advantage for Hyper-ion products.

Risen Energy's journey in ultra-thin wafer development addresses the industry's urgency to lower costs while maintaining a profound understanding of technological processes and a system-oriented innovative approach. By revisiting and sharing insights from Risen Energy's technical whitepaper, we aim to illustrate the latest milestones in our technological progression and to partner with industry players in propelling photovoltaic technology toward future products that are lighter, stronger, and more revolutionary than ever before.