Exceeding conversion efficiency of 26% by heterojunction interdigitated back contact solar cell with thin film Si technology

- Conversion efficiency of 26.6% achieved by heterojunction back contact (HJ-IBC) solar cell.
- This result was obtained using CZ silicon wafer.
- 0.3% absolute improvement in efficiency from the previous record is mainly driven by low series resistance.
- As further development from 26.6%, pseudo FF of 86.6% is obtained from SunsVOC of the newly developed HJ-IBC cell.

We have developed heterojunction interdigitated back contact solar cell with conversion efficiency of 26.6% (designated area: 180 cm2) independently confirmed by Fraunhofer Institute for Solar Energysystem Callab. Compared to our previous record efficiency (26.3%), the 0.3% absolute improvement can be regarded as ~10% reduction of remaining losses to the theoretical limit (~ 29%). We discuss the analyzed cell properties together with our recent progress to predict how far we can go in reducing the remaining losses in silicon photovoltaic.