Chinese solar module manufacturer JinkoSolar has set a new world record for n-type TOPCon solar cell efficiency, achieving 27.79%, according to independent verification from the Institute for Solar Energy Research Hamelin (ISFH) in Germany.

The milestone surpasses the company’s previous record of 27.02%, achieved in June for the same 182 mm n-type cell format and certified by China’s National Photovoltaic Industry Measurement and Testing Center (NPVM).

JinkoSolar attributed the performance boost to an ultrathin silicon oxide tunneling layer combined with doped polysilicon passivated contacts, a structure that significantly reduces carrier recombination. Additional gains were enabled by improved passivation materials, lower optical losses, and upgraded metallization processes.

In June, the company highlighted a proprietary hydrogenation process, developed in collaboration with unnamed R&D partners, as a key contributor to efficiency improvements—alongside ultrafine metallization, an advanced diffusion process, and multiple material enhancements.

The company’s progress has been rapid: as recently as October 2022, efficiency for this device stood at 26.1%.

JinkoSolar expects TOPCon cell efficiency to exceed 28% by 2028, according to projections shared in a recent white paper.

The manufacturer is also advancing tandem solar technologies. In January, JinkoSolar achieved 33.84% power conversion efficiency for an n-type wafer-based perovskite–silicon tandem solar cell. The results were certified by the Shanghai Institute of Microsystem and Information Technology under the Chinese Academy of Sciences (CAS). The company had previously reported an efficiency of 33.24% for the same cell configuration.