Title:	Interconnection Approach for Busbar-Less IBC Cells Based on Printed Solder Paste
Author(s):	T. Messmer, H. Chu, V.D. Mihailetchi, R. Roescu, J. Libal, A. Halm
Keywords:	Back Contact, Module Integration, PV Module, Busbar-less
Topic:	Photovoltaic Modules and BoS Components
Subtopic:	PV Module Design and Manufacturing
Event:	8th World Conference on Photovoltaic Energy Conversion
Session:	3DV.1.21
Pages:	837 - 841
ISBN:	3-936338-86-8
Paper DOI:	10.4229/WCPEC-82022-3DV.1.21
Price:	0,00 EUR
Document(s):	paper

Abstract/Summary:

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To decrease the cost for the interdigitated back contact (IBC) cell ZEBRA, a busbar-less interconnection approach is developed in order to reduce the silver consumption. Since the metallization for both polarities is printed on the backside of the cell, a 3D designed metallization layout is used for the ZEBRA cell. Thus, for a busbar-less interconnection approach, the wires must be individually contacted to the fingers between the insulation paste pads, which are printed to insulate the wire from the opposite polarity. Due to the individual contact of the fingers to the wire, the connection area is very small, resulting in a low adhesion between the fingers and the wire, which indicates low reliability of the interconnection approach. A reliable busbar-less interconnection approach is demonstrated by implementing finger pads below the solder paste pads. Due to the finger pads, the connection area between the wire and the fingers is increased, resulting in a higher adhesion. Moreover, it is shown that the reliability of the interconnection approach without finger pads can be significantly increased by adding an adhesion in order to mechanically attach the wires to the cell.