Efficiency Surpasses 30% & Module Power Exceeds 800W: China's PV Industry Enters the "Tandem Era"

China's photovoltaic (PV) technological innovation witnessed a "boom period" in 2025: in late October, a joint research team from Nanjing University and the National Innovation Institute of Defense Technology achieved a breakthrough in all-perovskite tandem solar cell efficiency, reaching 30.1% and setting a new global record.    Three months later, Trina Solar announced that its 210mm large-size perovskite-silicon tandem module had exceeded 800W in power, officially kicking off the industrialization process.    This "dual breakthrough"—from basic scientific research to industrial application—marks China's PV industry is transitioning from "leading in scale" to a new stage of "technological dominance".

"Microscopic Revolution" in Labs: Terahertz Technology Solves Efficiency Bottlenecks

"We used to work like 'touching an elephant blindfolded', but now we can clearly observe every movement of charge carriers," said the team led by Tan Hairen from Nanjing University.    On October 28, the team published a paper in Nature revealing that, in collaboration with Chang Chao's team, they developed a terahertz radiation detection technology.    This technology enables picosecond-level precise observation of charge carrier behavior inside perovskite materials—earning it the nickname "PV microscope" in the industry—and finally identified the key obstacle to efficiency improvement: charge carrier loss at the interface between the perovskite light-absorbing layer and the transport layer.

To address this pain point, the team designed a dipole passivation layer similar to a "one-way lane" to guide the directional migration of charge carriers.    Experimental data showed that after optimization, the charge carrier mobility increased by 68% and the diffusion length extended by 30%.    Eventually, the efficiency of the all-perovskite tandem cell reached 30.1%, making it the first technology of its kind in the world to break the 30% threshold.    This achievement has been included in the international Solar Cell Efficiency Tables.    "It's like installing a 'turbocharger' on PV cells, which is expected to reduce the levelized cost of electricity (LCOE) by another 18%," commented Wang Shijiang, Deputy Secretary-General of the China Photovoltaic Industry Association (CPIA).

"Scale Leap" in Workshops: 800W Modules Open the Door to Industrialization

If laboratory breakthroughs represent "point-based progress", the technological transformation by enterprises has achieved "area-wide coverage".    In March, Trina Solar announced that its 210mm standard-size perovskite-silicon tandem module had reached 808W in power, becoming the world's first industrial-grade product to exceed the 800W threshold.    Behind this achievement lies a decade of R&D efforts by the company, resulting in 331 related patents, as well as an industry-academia-research innovation system co-established with universities including Nanjing University.

"We overcame 17 process challenges to transform laboratory samples into mass-produced modules," revealed Gao Jifan, Chairman of Trina Solar.    The mass production line for these modules has entered the equipment commissioning phase, with an expected capacity of 5GW by 2026.

"Offensive and Defensive Game" in Patent Wars: Ecological Shortcomings Need to Be Addressed for Technological Leadership

While technological breakthroughs are being made, the "shortcoming" in patent layout has become increasingly prominent.    The White Paper on PV Industry Intellectual Property released in April shows that China accounts for 57% of global PV patent applications—with Jiangsu Province alone recording 43,696 patent sets.    However, overseas patents account for less than 1/10 of China's total.    In 2024, seven out of the world's top 10 PV module manufacturers were involved in patent disputes, with claims exceeding 1 billion yuan (approximately 137 million US dollars).

"One out of every three global TOPCon patents comes from Jiangsu, but the homogenization rate exceeds 40%," pointed out Fan Guoyuan, Secretary-General of the Jiangsu Photovoltaic Industry Association.    He noted that the current technological innovation is facing a dilemma of "internal homogenization competition in China, while lacking protection overseas".    In response, the industry has launched countermeasures: enterprises such as Longi Green Energy and Trina Solar are promoting the "Global Patent Network Initiative" to build a combination of "core patents + peripheral patents" in European and American markets.    Additionally, a government-enterprise joint "PV Patent Early Warning Platform" is about to be launched, providing enterprises with real-time litigation mon