A key reason for opposing involution in photovoltaics (PV) sector is to prevent such cutthroat rivalry from compromising product quality, which will not only undermine years of market cultivation, but also tarnish the reputation of China's PV industry. Therefore, evaluating whether an enterprise can uphold long-termism and sustainable operation depends on its adherence to quality standards during critical periods.

Regardless of competition intensity, Tongwei's product quality—whether in silicon materials, cells, or modules—remains exceptionally robust. In its mid-term performance forecast, the company stated that despite "persistent industry supply-demand imbalance and continuously depressed product prices across segments," Tongwei, as a dual leader in silicon materials and cells, maintains strong R&D investment to enhance product competitiveness, "ensuring stable operations and sustaining core advantages across multiple PV business segments."

During this year's Intersolar Europe, Tongwei simultaneously launched its new TNC 2.0 module products in Munich, Germany, and Yantai, China.

TNC (Tongwei N-passivated Contact Cell) applies an N-type passivated contact technical route, incorporating Tongwei's proprietary PECVD poly deposition technology to advance PV conversion efficiency.

In power output, Tongwei's TNC 2.0 modules excel. Based on the 908 technology platform, they have repeatedly set industry power records. Notably, the TNC G12R-66 variant achieves a peak power of 682.8W—60W higher than mainstream counterparts—while the TNC G12-66 variant reaches 778.5W, demonstrating significant size-based advantages.

It is worth mentioning that during this year's Shanghai SNEC, the bifaciality of Tongwei TOPCon modules in terms of technology R&D has already exceeded 88%; recently, Tongwei Global Innovation R&D Center demonstrated its latest technological breakthrough—ultra-high bifaciality solar modules based on tunnel oxide passivated contact (TOPCon) technology, which has achieved a cell bifaciality breakthrough of 94.3% (certified by TÜV Rheinland from Germany), a module bifaciality of 91.7%, and a module power output of up to 722W. This sets the industry's highest module bifaciality level!

Tongwei TNC Module

01

Four Core Technologies Boost TNC 2.0 Efficiency

Unlike conventional launches, Tongwei concurrently released the Tongwei TNC Module Technology White Paper, detailing TNC 2.0's efficiency solutions.

It mainly includes four key technologies: 908 technology (Tongwei's independently developed 0BB technology), TPE technology, Poly Tech, and steel screen printing.

Among them, 908 technology is Tongwei's independently developed 0BB cell technology, which is a new type of component interconnection technology. This technology was completed in 2024 and was first mass-produced and introduced on the TNC 2.0 product.

Its multi-wire approach increases power output while reducing internal stress (30% lower microcrack risk) via flexible cell connections. The welding process can form good ohmic contact, and the thermosetting adhesive closely bonds the solder tape and the battery, which enhances the ability of the module to resist cold and heat shock, load, and hot spot risks during actual use, thereby improving the reliability of the modules.

Beyond advancements in module technology, the TNC 2.0 module incorporates high-efficiency cells that integrate multiple advanced efficiency-enhancing technologies.

Regarding cell processing, the utilization of specially designed steel plates, replacing traditional screen printing, achieves a 100% aperture ratio while reducing shading area by 3.3% and enhancing current collection capability on the cell surface.

In terms of cell structure, the removal of the Poly layer in the non-contact area ensures passivation and contact performance, reducing optical losses and improving module power and bifaciality. Simultaneously, the adoption of optimized passivation materials treats the sides generated by cell laser cutting, repairing edge defects caused by cell cutting, resulting in a dual significant enhancement in cell power generation performance and long-term reliability.

New technologies facilitate the iterative upgrade of Tongwei TNC series products, with Tongwei TNC 2.0 product modules increasing power by over 20W and bifaciality by 5%-10%.

Tongwei modules have always prioritized safety and reliability, having passed multiple stringent reliability test sequences.

Taking the large-format G12R-66 module product as an example, this product has obtained stringent certification certificates such as IEC TS 63209 enhanced test and IEC TS 63126 high-temperature environment enhanced test, and received the "Top Module Manufacturer" honor in the 2024 "PVEL PV Module Scorecard." Test items include 3x thermal cycle testing (TC600), 2x damp heat testing (DH2000h), 2x potential-induced degradation testing (PID192h), 3x light and elevated temperature-induced degradation testing (LeTID486h), 120kWh/m2 UV degradation testing, composite dynamic and static load testing, and 40mm hail testing, among a series of enhanced reliability tests.

02

Pioneering PECVD: The Rise of an Industry Standard

In the Tongwei TNC Module Technology White Paper, Tongwei emphasizes its foundational technology platform and standard technical configurations.

In terms of the cell platform:, both Tongwei's TNC 1.0 and TNC 2.0 cells adopt the independently developed, industry-leading PECVD polysilicon deposition technology route, combined with efficient secondary sintering technology, to achieve high-quality metal contact without damaging the passivation layer of the non-contact area.

It's worthwhile to revisit PECVD's evolutionary journey here.

TOPCon cell technology currently follows two main industrialization paths—PECVD and LPCVD—differentiated by their methods of preparing tunnel oxide layers and doped polysilicon. These two technological routes have engaged in competitive, spiral development.

JinkoSolar and Hainan Drinda Automotive Trim are leading proponents of LPCVD. And LPCVD also constitutes the primary product of equipment newcomer Laplace.

Tongwei, on the other hand, is the leader in the industrialization of TOPCon PECVD technology. In mid-2021, Tongwei successfully developed the industry's first large-size PECVD Poly deposition technology route and achieved mass production of this route the following year.

With advantages including higher poly-Si efficiency potential, faster deposition rates, minimal edge deposition, extended quartz component lifespan, and superior production capacity, PECVD has now become the industry's mainstream choice, commanding over 50% market share.

Tongwei's secondary sintering process represents an innovative contact formation technology that enhances metal-semiconductor interfaces. It improves solar cell electrical performance while enabling holistic fine-tuning of the entire process sequence, resulting in more uniform contact resistivity and balanced fill factor distribution.

For module platforms, both TNC 1.0 and TNC 2.0 cells incorporate cutting-edge technologies like gap film lamination and double-glass designs. These innovations maintain exceptional module reliability while further optimizing efficiency and power output. Currently, TNC 1.0 modules achieve maximum mass production efficiency of 23.3%, while TNC 2.0 modules show approximately 1.0%+ efficiency improvement over their predecessors.

The company's 2024 annual report states that "Tongwei continues to advance TNC technology through efficiency gains and cost reductions. By optimizing production cycles, upgrading screen patterns, recycling chemicals, and adopting domestic pastes, we consistently set industry benchmarks in single-line capacity, Grade A rates, conversion efficiency, and non-silicon costs."

03

RMB 11 Billion R&D Investment Over Three Years!

The advent of TNC 2.0 has accelerated Tongwei's global expansion In the first half of this year, Tongwei Co., Ltd. has signed cooperation agreements with multiple global partners, covering key photovoltaic markets in Europe, Asia-Pacific, and Africa, with successful implementations in France, Italy, the Netherlands, Pakistan, Japan, South Africa, Poland, and Germany.

TNC 2.0, a new product developed by Tongwei Co., Ltd., represents another achievement in cell technology transformation. The company's R&D efforts extend far beyond this.

Regarding PV cells, the company's annual report states that "In 2024, we will grasp the iteration rhythm of N-type technology and accelerate the adjustment of production capacity structure, with the current TNC cell capacity reaching 150GW. The total sales of solar cells in 2024 reached 87.68GW (including self-use), a year-on-year increase of 8.70%. According to InfoLink Consulting data, Tongwei has topped the global cell shipment list for eight consecutive years, with a global market share of approximately 14% in 2024."

Tongwei has always prioritized R&D investment. As explained by Chief Technology Officer Xing Guoqiang, the company imposes no upper limit on R&D expenditures. Announcements show that Tongwei's cumulative R&D investment has exceeded RMB 11 billion in the past three years.

Source: WIND; Unit: RMB

Substantial R&D investment, coupled with exceptional execution capabilities, has enabled Tongwei's leapfrog development in PV modules. Since fully entering the module sector in 2022, Tongwei has surpassed 100GW in module shipments. Public information indicates that Tongwei has established four major production bases of TW Solar Technology in Hefei, Yancheng, Jintang, and Nantong.

In 2024, Tongwei Global Innovation R&D Center officially commenced operations. As the company stated in its annual report, through pioneering research initiatives and industry-academia collaboration projects, the company has established achievement transformation bases and engineering talent cultivation bases, continuously exploring uncharted technological territories. Concurrently, the company jointly established the Sichuan Province Crystalline Silicon Photovoltaic Industry Innovation Center with multiple leading enterprises, integrating resources to build an industrial innovation ecosystem. This initiative aligns with national strategic priorities and international cutting-edge technologies to address critical "bottleneck" challenges, creating a multi-track, multi-dimensional collaborative R&D system.

In the future, Tongwei's R&D Center will closely follow corporate development strategies to advance high-efficiency crystalline silicon cells and highly reliable module products. Its research scope comprehensively covers future photovoltaic technologies including TNC, THC, TBC cells/modules, perovskite/silicon tandem solar cells/modules, and copper interconnection metallization, providing technological assurance and traction for the company's industrial development over the next five years and beyond.