The research results were published in the report "Buyer aware: Three new failure modules in TOPCon modules absent from PERC technology". The researchers tested a series of TOPCon and PERC components with different compositions to determine how exposure to humid thermal environments affects the performance of the components.

It was also because of this test that the research team discovered that TOPCon components (especially single-glass backsheets) had three failure types that did not exist in PERC components before, which deserve the attention of the industry.

In this environment, component changes have little impact on component performance, but using TOPCon versus PERC technology makes a significant difference. The R&D team conducted more than 1,000 hours of testing (Damp Heat Test) on PERC and TOPCon modules encapsulated with different adhesive films in a hot and humid environment.

Test results show that the power loss of PERC modules is only 1-2%, while TOPCon modules are sensitive to film quality, and their power attenuation ranges from 4-65%, which is a big difference and a wider range.

The research team believes that "electrochemical reactions involving moisture" may be responsible for the poor performance of TOPCon modules.

The three types of failures observed in TOPCon components are: the first is point-localized failure (Type-1), which is characterized by EL local black spot problems at different stages of the DH test. This type of failure may It is attributed to the electrochemical reaction between moisture, contaminants present on the battery before packaging, and the battery metal.

The second is the failure mode that occurs at/around the interconnection point between ribbon wires and busbars of the cells (Type-2). Fault.

As the DH test progresses and gradually expands to the surrounding cell area, this type of failure mode will cause the Rs of the module to increase. Further analysis revealed that this failure mode could be caused by electrochemical reactions between moisture, solder ribbon, busbars and flux, leading to metal corrosion.

The third category is complete failure across the entire area of the cells/modules (Type-3). In some film-encapsulated TOPCon components, a Type-2 failure type will appear followed by The test continued, and the failure area gradually expanded to more surrounding areas and even the entire battery area.

While the researchers note that the specific contaminants causing the power drop are "currently unknown," they speculate that the presence of sodium and chlorine on solar modules, spread from human fingertips during assembly and shipping, may have a negative impact on TOPCon cells. The impact is that TOPCon cells are more susceptible to potential risks when exposed to high humidity and contaminants before packaging, and these cells were "found to be particularly vulnerable."

This could be a significant discovery as TOPCon modules are expected to become more common in the global solar landscape.

In the report, the researchers wrote: "Extensive and in-depth research is urgently needed to significantly improve our understanding of TOPCon cells and enhance their reliability under the influence of moisture and other contaminants." The report highlights further research into TOPCon components The importance of performance in wet environments.trina solar panels