Comparison of Commercial TOPCon PV Modules in Accelerated Aging Tests

Tunnel oxide passivated contact (TOPCon) is set to become the new mainstream cell technology despite pending reliability concerns. This work compares commercially available TOPCon photovoltaic (PV) module types from five different manufacturers in a variety of electrical characterization and accelerated aging tests. This case study represents a selection process of PV modules for larger PV installations. Therefore, the work features an in-depth comparison of the electrical performance (energy rating) that can serve as a reference for state-of-the-art TOPCon modules. The aging results confirm previously reported degradation mechanisms of the TOPCon technology due to humidity ingress. In the case of UV aging, a new pattern of strong degradation (up to –12% after 60 kWh/m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>;) and subsequent recovery after humidity freeze test is presented, which could have implications on the results of certification tests (IEC61730-2, Sequence B). Though not directly connected to the TOPCon cell technology, the mechanical load tests revealed weaknesses of several module types, related to module dimensions, frame height, and glass properties. Based on the results, the necessity for more focused testing and technological development is highlighted.