HJT Fully Made in China

Huasun Energy Co., Ltd held an inauguration ceremony for its new 500 MW HJT fab on April 23, 2021. The event followed on the commissioning of the line on March 30 (see Huasun Achieves 24.39% Highest Efficiency For HJT Cell). Within a short 9 month period after the company registered on 21 July,2020, the Chinese company has executed the project at a remarkable pace.
The installed capacity of 500 MW is achieved through two production lines each with 250 MW capacity. Of these, one line is completely supplied by rising equipment supplier in the HJT field, Maxwell, which has supplied all necessary key production tools for HJT cell production – wet-chemical benches, PECVD, PVD and screen printers. The line has a rated throughput of 8,000 wafers per hour, which is also referred to the throughput of the PECVD, which is the fastest so far. Huasun underscores that this line is also a ‘verification site’ for a high throughput HJT production line built completely with “domestic” equipment. The second line consists of an assorted pool of suppliers, namely wet-benches from YAC, Japan; Ideal Sunrise’s PECVD; Germany’s Von Ardenne providing the PVD; and screen printers from Zonchow. The line is equipped with a MES.
As for the most important process consumable and cost contributor, the low temperature cured silver pastes, Huasun is relying on Japan’s Kyoto Elex. An inherent limitation of HJT is its requirement for higher amounts of silver pastes compared to traditional PERC cells. This is due to its polymeric base to compensate conductivity. In order to circumvent this issue, Huasun is employing a 12-busbar layout in screen printing and reduced the consumption to 140 mg referring to M6, which is also the reference size for all above parameters. Within few days after commissioning, Huasun said it had achieved a single daily average mass production efficiency of 24.12%, while 24.4% was the highest level of an average single batch during a day. It said its champion production cell efficiency is 24.73%.
At the module level, the company is adapting the combination of half cell and MBB layout. As it is common these days, Huasun is using a non-destructive cutting method for slicing its cells. The innovation at module level is that the company is using two different kinds of ribbons – a circular interconnect on the front side to compensate the shading losses due to a higher number of busbars, while a flat ribbon is still used on the rear side. Having 12 busbars on a M6 cell size also requires a very high positioning accuracy at the soldering station. Maxwell has also supplied such a stringer. Huasun also received TUV certification for its modules products that come in cell layouts with 120 (60-cell equivalent), 132 (66-cell equivalent) and 144 (72-cell equivalent) cells. According to the presentation at the event, the top of the range has a labelled wattage of 470 W and a module efficiency of 21.6%.
As part of its future plans, Huasun has purchased an R&D line for adapting the HJT process for the G12 wafer format, which will be put into use during Q2 and Q3. In parallel, the company said it is aiming to reach average efficiency of 24.5% this year. Huasun also has big plans for expanding production capacity to 2 GW, for which the HJT maker is planning to move-in the necessary production equipment before end of Q4 2021. And like any other HJT maker, Huasun also has a HJT-tandem cell architecture on it  roadmap – it wants to attain efficiencies in the range of 28% in about 4 years.
Cost wise, Huasun estimates to reduce the production costs 0.712 RMB/W by end of this year from an estimated level of 0.95 RMB/W in 2020 by means of material and process optimization. In order to reduce the costs further, the company is evaluating the usage of a silver coated copper particle paste compositive, which is expected to reduce the costs even to a little lower level than PERC, down to 0.65 RMB/W by next year.

Cost reduction potential: Huasun has an aggressive plan to reduce the costs of HJT by means of several optimization measures and especially employing silver coated copper particles based paste as is presented at the official factory inauguration day (source: Huasun)