Improving the photoconversion eciency of silicon solar cells is crucial to further the deployment of renewable electricity.Essential device properties such as lifetime, series resistance and optical properties must be improved simultaneously toreduce recombination, resistive and optical losses. Here, we use industrially compatible processes to fabricate large-areasilicon solar cells combining interdigitated back contacts and an amorphous silicon/crystalline silicon heterojunction. Thephotoconversion eciency is over 26% with a 180.4 cm2 designated area, which is an improvement of 2.7% relative to theprevious record eciency of 25.6%. The cell was analysed to characterize lifetime, quantum eciency, and series resistance,which are essential elements for conversion eciency. Finally, a loss analysis pinpoints a path to approach the theoreticalconversion eciency limit of Si solar cells, 29.1%.