Bifacial IFO/(n+pp+)Cz-Si/ITO silicon solar cell with advanced Ag-free multi-wire metallization attached to TCO layers by transparent conductive PAES copolymers

• Published in: Solar energy 2018-04, Vol.164, p.292-300
• Main Authors: Chebotareva, A.B., Untila, G.G., Kost, T.N., Stepanov, A.S., Salazkin, S.N., Shaposhnikova, V.V.
• Format: Article
• Language: English
• Subjects: Ag-free multi-wire metallization; C band; Chemical synthesis; Conductivity; Copolymers; Fluorene; Glass transition temperature; Indium oxides; Metal oxides; Metallizing; Peel strength; Photovoltaic cells; Photovoltaics; Polyarylene ether sulfone; Polymer films; Polymers; Refractivity; Silicon; Silicon solar cell; Solar cells; Solar energy; Thermoplastic resins; Transition temperatures; Transparent conductive oxide; Transparent conductive polymer; Wire
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2018.02.067

[Display omitted] •Transparent conductive poly(arylene ether sulfone) copolymers were synthesized.•Thermomechanical and optical properties of co-PAES films were investigated.•The best resistivity of wire/co-PAES/TCO contact was about 0.43 mΩ cm2.•Co-PAES films were used in bifacial IFO/(n+pp+)Cz-Si/ITO LGCell.•Front/rear efficiencies of 18.2%/15.1% were achieved for LGCell. Multi-wire metallization and interconnection for silicon solar cells is considered as a revolutionary technology for the next generation of photovoltaic modules, since it drastically reduces their cost while boosting efficiency. Here, we describe the synthesis, properties and application of transparent conductive polymer films, poly(arylene ether sulfone) copolymers (co-PAESs), for attaching the wires to solar cells with transparent conductive oxide (TCO) layers. We have synthesized a number of thermoplastics with the fraction of fluorene-containing units q = 3, 5, 10, 15, and 50 mol%. Increasing q has been shown to change the glass transition temperature of the copolymers from 186 to 232 °C, their 100% strain temperature from 240 to 320 °C, their optical band gap from 3.80 to 3.77 eV, and their refractive index from 1.554 to 1.586. At that, absorption in the wavelength range 370–1100 nm is negligible, the resistivity and the peel strength of wire/co-PAES/TCO (TCO: ITO = In2O3:Sn and IFO = In2O3:F) contacts lies within 0.43–2.7 mΩ cm2 and 2.7–3.0 N/mm, respectively. The co-PAES film with q = 10 mol% was successfully used to attach wire contact grid in bifacial IFO/(n+pp+)Cz-Si/ITO solar cell, which showed a front/rear efficiency of 18.2%/15.1% under 1 sun illumination.