Electrically Conductive Adhesive as Cell Interconnection Material in Shingled -Henkel

Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology L.Theunissen, J. Burke, B. Willems, A. Henckens J. Zhang, L. Zhao, Q. Fu Chang Zhou, August 20182 Who we are The Largest Adhesives Supplier in the World Adhesive Technologies Laundry & Home Care Beauty Care Industrial Business Consumer Businesses 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology3 Adhesive Technologies Five Business Areas Packaging And Consumer Goods Transport and Metal General Industry Electronics Consumer, Craftsmen and Building 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology4 Electronic Adhesive Technologies Expertise in customizing highly filled polymeric systems 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology Semicon- ductor Materials Display Materials Encapsulation Component Assembly Printed Electronics Soldering Thermal Management Device Assembly Equipment ▪ Highly customized materials for key applications and customers ▪ Very broad portfolio of chemistries expertise: Epoxy, Acrylate, Silicone, Bismaleimide and Hybrid. ▪ Over 30% of sales come from products launched within the last 5 years. ▪ and the largest market share globally.5 Henkel’s dedicated Solar Business Infrastructure, providing local support worldwide R&D Manufacturing Sales and Engineering Support R&D/Manufacturing/Sales and Engineering Support Headquarters: Irvine, CA USA Serving Our Solar Customers Worldwide Global End-to-End Business Infrastructure for Solar Customers6 Technical Centers Global coverage 7/26/2018 ▪ Over 500 PD&E globally for Electronics customers ▪ Multiple technical centers worldwide US: Irvine, Chanhassen APAC: Shanghai, Singapore, Taiwan, Isogo, Seoul Europe: Westerlo, Hemel Formulation Lab Application Lab Reliability Lab Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology7 Solar Test Capabilities Westerlo, Belgium / Shanghai, China IV tester Peel tester 3D microscope Laminator VR/CR tester Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology Printer 7/26/20188 Shingled Module Technology Introduction 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology Conventional Module: c-Si Cell interconnect in serie by solder (PbAg) coated copper ribbon Shingled Module: c-Si cell interconnect of shingles and ribbons by Electrically Conductive Adhesive (ECA) 9 Shingled Module Technology Value Drivers ▪ Power output ▪ 10% power increase ▪ Reduced Ohmic losses ▪ Optimized cell/Module active area = Tighter cell packing ▪ Cell ▪ Thinner cells ▪ All cell technologies work ▪ Reduced metallization 7/26/2018 ▪ Reliability ▪ Reliable interconnect ▪ No residual stress between Si and metal ▪ Energy Yield ▪ Lower hotspot temperature ▪ No shading ▪ Aesthetics Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology10 Why use electrically conductive adhesives (ECA) for shingling? ▪ Reliable interconnect ▪ High Stress absorbance ▪ CTE mismatches in modules can be absorbed by ECA ▪ Survive mechanical load testing ▪ Low processing temperatures ▪ Temperatures between 110° C-180° C ▪ Reduced bowing of cell at curing temperatures of ECA ▪ Process simplicity ▪ Environmental ▪ No lead containing solder 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology11 Material properties 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology Property Units ECA-A ECA-B Bulk resistivity Ohm.cm 2.10 -4 2.10 -3 Tensile Lap Shear Strength (Al/Al) MPa 11.5 10 -modulus at -50° C -modulus at 25° C MPa 12000 4900 6645 1388 Cr-Ag ribbon mOhm 2 6 Cr-Ag ribbon after 3000 hours 85° C/85%RH mOhm 2 12 Cr-Ag ribbon after 300c -40° C/85° C mOhm 3 6 Cr-Sn ribbon mOhm 16 NA Cr-Sn ribbon after 3000 hours 85° C/85%RH mOhm 15 NA Cr-Sn ribbon after 300c -40° C/85° C mOhm 20 NA Reactivity ° C 84 72 Density g/cc 4,4 1,9 In presented builds ECA-A is used as SnPb ribbon attach and shingle attach. ECA-B is used as shingle attach.12 Application Techniques 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology13 Mini-module/Module build 7/26/2018 Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology Cell type m-crystalline PERC 5 shingles/cell m-crystalline PERC 6 shingles/cell Shingle overlay 1.8mm 1.5mm Pad dimensions Varied number of pad of 5 mm x 0.35 or full line 11 pads of 4 mm by 0.75 mm Shingle attach ECA-A or ECA-B ECA-A or ECA-B Ribbon attach ECA-A Soldering Application method Print/dispense Print14 Influence ECA deposit on module performance 7/26/2018 ➢ No large Power output reduction for both materials upon reducing weight per shingle 4.500 4.550 4.600 4.650 4.700 4.750 4.800 0 25 50 75 100 Pmax (W) % relative amount ECA/cell ECA-B ECA-A 74.0 74.5 75.0 75.5 76.0 76.5 77.0 0 25 50 75 100 FF % % relative amount ECA/cell ECA-B ECA-A Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology15 Thermocycle performance -40° C/85° C Mini-modules 7/26/2018 ➢ Below 1% reduction in Pmax for both Acrylate ECA ➢ No influence of application technique on Power output and reliability performance is seen -1.50% -1.25% -1.00% -0.75% -0.50% -0.25% 0.00% TC0 TC 250 TC 600 Pmax (%) ECA-A dispensed line 96% rel weight/cell ECA-A printed 9 pads 44%rel weight/cell ECA-A printed line 100% rel weight/cell ECA-B dispensed line 48% rel weight/cell ECA-B printed line 50% rel weight/cell ECA-B printed 9 pads 22% rel weight/cell Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology16 Thermocycle performance -40° C/85° C Module 7/26/2018 ➢ Below 1% reduction in Pmax for both Acrylate ECA -3.0% -2.5% -2.0% -1.5% -1.0% -0.5% 0.0% 0.5% 1.0% TC 0 TC 100 TC 200 Pmax % ECA-A ECA-B Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology17 Timeline H1 H2 H1 H2 H1 H2 2020 2121 Application Method Applications Substrates Usage per 60 cell Solar Module $/W cost of ECA 2017 2018 2019 2020 2021 3.8 Gram 2.2 Gram Henkel Electrically Conductive Adhesive Road Map Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology GEN 2 ECA GEN 3 ECA 1.2 Gram 1.6 Gram $0.012/W $0.005/W $0.003/W $0.007/W GEN 1 ECA Full busbar Full Busbar, Psuedo Busbar ITO & SiNx Compatability Busbarless Dispense & Print 180mm/sec Screen & Stencil Print Jet Dispense 250 mm/sec Screen & Stencil Print Jet Dispense 350-450 mm/sec Shingle, Shingle Ribbon Attach Shingle, Shingle Ribbon Attach, Heterojunction Ribbon Attach Busbarless Application for HJT & Shingle 7/26/2018 GEN 4 ECA18 Conclusions 7/26/2018 • Shingle Panel Designs dictate which ECA properties are needed • Henkel offers ECAs based on different chemistries and properties customized for each design • High speed print and dispense speeds obtained ( 200 mm/sec) • Proven module reliability with acrylic based ECA both for shingle as well as standard SnPb ribbon string attachment • • shingle overlap, low ECA usage and low cost for the next generation of solar panels! Electrically Conductive Adhesives as Cell Interconnection Material in Shingled Module Technology