Maxwell has announced that it has achieved a photoelectric conversion efficiency of 25.62% on a full size (M6, 274.5cm²) HJT cell, using low-indium transparent conductive oxides (TCO) combined with silver-coated copper paste, creating a new world record certified by the Institute for Solar Energy Research (ISFH) in Germany.
This latest technology ensures considerably higher efficiency for HJT cells in mass production and a significant cost reduction. The 144-half-size-M6-cell based HJT module developed by Maxwell’s module technology laboratory has been tested, with the resultant power of 491.8W 30W higher than that of a PERC module of the same size. The primary reference cells are from TÜV Rheinland, Germany.
The use of indium in the cell can be reduced by 50% through a new low-indium solution which adopts magnetron sputtering. A further 40% reduction can be achieved with the introduction of indium decreasing equipment, making 30% of current levels realistic. In addition, the consumption of silver can be lowered by 55% through silver-coated copper paste, the combination of the two processes alone dramatically cutting the manufacturing cost of HJT cells.
Maxwell’s module technology laboratory can independently carry out manufacturing and electrical performance testing of high-efficiency HJT modules, which plays an important role in reliability assessment and process optimization. The latest batch of test cells adopted an SMBB (Super Multi Bus Bar) stringer and a special water-blocking encapsulation process to optimize soldering quality and reduce mechanical damage. This enabled the efficiency of the cells to increase to 22.62%, equivalent to the highest efficiency of HJT modules with conventional levels of precious metal content.
To promote the mass production and application of HJT technology, Maxwell continues to develop cost-efficient solutions for halving and thinning N-type silicon wafers and decreasing the use of silver paste and other precious metals. At the same time, the company is stepping up efforts to improve the mass production efficiency of HJT cells and modules through micro-crystallization, metallization, SMBB and light conversion technology.
This latest technological breakthrough represents a realistic solution for cost reduction and efficiency increase in HJT products in the photovoltaic industry. It will significantly accelerate the industrialization of HJT cells and modules and help reduce the LCOE of solar power in pursuit of achieving the dual goals of carbon peaking and subsequent neutrality.