Towards 22% efficient screen-printed bifacial n-type silicon solar cells

Abstract This paper outlines the development of fully screen-printed, uniformly diffused, bifacial, n-type silicon solar cells produced using a lean processing sequence and industry-standard equipment. An average batch efficiency of 21.4% was measured at standard test conditions for an optimised bifacial cell batch (i.e. illumination on the front surface only). The results of open circuit voltage (VOC) and fill factor (FF) loss analyses are presented for select batches. By targeting reductions in the largest recombination components, optimised batch VOC was increased by 15 mV compared to the baseline case. The two largest recombination components limiting VOC in optimised devices are front contact recombination and passivated rear surface recombination. The largest FF loss components for optimised devices are the emitter sheet resistance and front contact resistance.

[1]  Prabir K. Basu,et al.  A Fill Factor Loss Analysis Method for Silicon Wafer Solar Cells , 2013, IEEE Journal of Photovoltaics.

[2]  Naoteru Matsubara,et al.  Achievement of More Than 25% Conversion Efficiency With Crystalline Silicon Heterojunction Solar Cell , 2014, IEEE Journal of Photovoltaics.

[3]  K. Yoshikawa,et al.  Silicon heterojunction solar cell with interdigitated back contacts for a photoconversion efficiency over 26% , 2017, Nature Energy.

[4]  Bifacial, fully screen-printed n-PERT solar cells with BF2 and B implanted emitters , 2016 .

[5]  G. Bunea,et al.  Silicon solar cells with total area efficiency above 25 % , 2016, 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC).

[6]  Y. Veschetti,et al.  Understanding of the annealing temperature impact on ion implanted bifacial n‐type solar cells to reach 20.3% efficiency , 2015 .

[7]  A. Aberle,et al.  A Systematic Loss Analysis Method for Rear-Passivated Silicon Solar Cells , 2015, IEEE Journal of Photovoltaics.

[8]  Chih-Jeng Huang,et al.  Improvement on Industrial n-type Bifacial Solar Cell with >20.6% Efficiency , 2014 .

[9]  Armin G. Aberle,et al.  A new method to characterize bifacial solar cells , 2014 .

[10]  S. Hultén,et al.  Escaping lock-in: The case of the electric vehicle☆ , 1996 .

[11]  Valentin D. Mihailetchi,et al.  A Comparison Study of n-type PERT and IBC Cell Concepts with Screen Printed Contacts , 2015 .

[12]  David D. Smith,et al.  Toward the Practical Limits of Silicon Solar Cells , 2014, IEEE Journal of Photovoltaics.

[13]  E. Wefringhaus,et al.  Progress in the development of industrial nPERT cells , 2017 .

[14]  P. David.  Clio and the Economics of QWERTY , 1985 .

[15]  H. H. Berger,et al.  Contact Resistance and Contact Resistivity , 1972 .

[16]  Taehyeon Kim,et al.  Bifacial solar photovoltaics – A technology review , 2016 .

[17]  J. Wong,et al.  Voltage Loss Analysis for Bifacial Silicon Solar Cells: Case for Two-Dimensional Large-Area Modeling , 2016, IEEE Journal of Photovoltaics.

[18]  D. Schroder,et al.  Solar cell contact resistance—A review , 1984, IEEE Transactions on Electron Devices.