Title:	Module Integration of SHJ Cells by Soldering
Author(s):	B. Commault, P. Lefillastre, S. Bernardis, A. Bettinelli, J. Diaz, M. Debourdeau, F. Pernoud
Topic:	Photovoltaic Modules and BoS Components
Subtopic:	PV Module Design, Manufacture, Performance and Reliability
Event:	36th European Photovoltaic Solar Energy Conference and Exhibition
Session:	4CO.3.6
ISBN:	3-936338-60-4
Price:	0,00 EUR
Document(s):	presentation

Abstract/Summary:

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The standard soldering interconnection process is more difficult on SHJ solar cells due to the mandatory use of low curing temperature silver pastes (1). Thus the standard interconnection process on SHJ cells is done by ribbons gluing (2). Our work focuses on the interconnection of silicon heterojunction (SHJ) solar cells by soldering with SnBiAg low temperature alloy and SnPbAg on different SHJ metallization pastes. The adhesion of the ribbons soldered on the SHJ cell is evaluated. Mini modules are the made to evaluate the reliability of the soldering interconnection after 50, 200 and 400 thermal cycles between -40°C and +85°C. We realized successful interconnection of SHJ solar cells both with low and standard temperature alloy with Pmax losses < 5% for five different test conditions. Keywords: Heterojunction, Interconnection, Soldering, Module, Thermal Cycling. INTRODUCTION: Heterojunction cells are very sensitive to temperatures higher than 200°C and the metallization of SHJ cells is done with low temperature silver polymer screen printed paste. These high efficiency cells are mainly interconnected by two low-temperature processes. The most conventional one consists to attach the copper ribbons with Electrically Conductive Adhesives (ECA) deposited on the cell’s busbars by screen printing or valve jetting. The second emerging process is the Smart Wire Connection Technology (SWCT), from Meyer Burger, which is based on the wires bonding of 250 μm wires coated with a low melting point alloy on the cell during the lamination step.