From November 2 to 4, 2023, the 15th China (Wuxi) International Renewable Energy Conference and Exhibition (CREC2023), co-sponsored by China Chamber of International Commerce, Jiangsu Council for the Promotion of International Trade and Wuxi Municipal People's Government, was held in Wuxi Taihu International Expo Center. Jointly explore the future trend of the development of renewable energy industry, explore the innovative direction of new energy technology, and jointly promote the development of renewable energy industry.

Winhitech,As a manufacturer and supplier with the holding background of central state-owned enterprises with the mission of leading the global heterojunction industrialization, was specially invited by the conference to participate in the keynote speech of the "HJT cell module Special Technical Sub- Forum". The representatives at the meeting shared Winhitech's current work of  in the aspect of cost reduction and efficiency increase of HJT modules, focusing on the development progress of Winhitech's 0BB technology. The sharing at the forum was well received by industry experts who showed great interest in Winhitech. This time Winhitech shared site of many enterprise audience photos in the CREC technology forum , forward-looking practices of the enterprise after the discussion, as well as the current HJT process technology, solutions and future development planning and prospects.

 Mainly through the three aspects of HJT module reliability,power improvement and 0BB cost reduction technology, the work of reducing costs and increasing efficiency of HJT modules is introduced.

Among them, for the reliability part, improvement plans and evaluation results are proposed respectively for three reliability problems currently such us HJT modules,  adhesion to the film,  water vapor corrosion resistance and UV resistance.

In addition, the technology of 0BB to reduce cost and increase efficiency is emphatically introduced.

At present, the mainstream 0BB technology mainly has three types of  technical routes.

1. Printing + laminated alloy. The main advantage is that the equipment production capacity is large, there are many equipment and material manufacturers delevoped,  and the resources are abunndant. but the disadvantage is that the cell and welding tape is physical contact at the beginning , string EL prone to black line phenomenon, which will be improved after lamination. in addition,  special adhesive film need to be used , the reliability and process stability of the  adhesive film  also need to be carefully evaluated.

2. Welding + dispensing method. The main advantage is that the EL effect is better after the equipment is in string, and the adhesive film used for packaging is lower than the printing solution. However, because the dispensing beat is slower than the printing, the equipment production capacity is lower than the printing solution.

3. Welding tape coating solution. The main advantage of this solution is to eliminate the UV glue and printing or dispensing process. However,the disadvantage is that the cells and welding tape are in physical contact at the beginning, and the string EL is prone to black line phenomenon.

Each of these three technical solutions has its advantages and disadvantages.

Cost reduction: It can break through the bottleneck of silicon wafer thinning, and HJT cost reduction is the most urgent demand.

Efficiency enhancement: Reduce the shading surface + shorten the current transmission path + improve the yield rate.

Through theoretical simulation and experimental verification, Winhitech has found that the current experimental power gain reaches about 1%, the comprehensive cost of the modules has been reduced by about 5 cents /W.Tthere is still room for further cost reduction by adding silver-coated copper slurry in the future . At the same time, the internal reliability assessment of 0BB technology has also been carried out, which is basically the same as the existing top technology. At the same time, we continue to pay close attention to the development of N-type module technology, including the research and development and innovation of perovskite stacked cells, and will continue to improve the technical application field for further development.