Screen-Printed Metallization Concepts for Large-Area Back-Contact Back-Junction Silicon Solar Cells

Abstract

In this study, we investigate three screen-printed metallization concepts for back-contact back-junction silicon solar cells with an edge length of 156 mm: 1) a busbar-less concept with periodically interrupted contact fingers for wire-based interconnection; 2) a single-layer concept with printed busbars and periodically interrupted contact fingers; and 3) a multilayer concept consisting of continuous contact fingers, an insulation layer, and busbar metallization. A comprehensive simulation study is presented for all investigated metallization concepts, yielding their respective performance loss mechanisms. The multilayer approach is found to provide superior conversion efficiencies η, compared with the single-layer approach. For the wire-based concept, we show that contact finger interruptions up to a width of 1 mm have no significant negative impact on cell performance (Δη < 0.1% ab s ). Furthermore, peel force measurements on test structures between soldered cell interconnectors and screen-printed metallization are discussed for the multilayer and the wire-based concept. Successful proof of principles with peel forces exceeding 1 N/mm are demonstrated for both investigated metallization concepts.

HIT Solar Cell Modeling Using Graphene as a Transparent Conductive Layer Considering the Atacama Desert Solar Spectrum

“…Solar cell modeling also considers the metallization of the front and back parts. The geometrical characteristics of the busbars and the fingers are shown in Table 3 [60,61].…”

“…Solar cell modeling also considers the metallization of the front and back parts. The geometrical characteristics of the busbars and the fingers are shown in Table 3 [60,61]. As reference, this study considers the approximate experimental values of the heterojunction solar cell a − Si : H/c − Si: open-circuit voltage V oc = 713 mV, short-circuit current density J sc = 37.3 mA/cm 2 , fill factor FF = 75.9%, and energy conversion efficiency η = 20.2%, as measured by Muñoz et al in their study [62,63].…”

Development of back-junction back-contact silicon solar cells based on industrial processes

“…Hendrichs et al . investigated three different screen‐printed metallization concepts for BJBC silicon solar cells with an edge length of 156 mm. They qualified the individual loss mechanisms of each metallization concept and the maximum solar cell conversion efficiency of 22.0% by means of numerical simulations.…”

Evaluation of screen-printed metallization concepts for large-area BC-BJ solar cells

“…The first concept, shown in Fig. 1a, is based on a multi-layer metallization approach [3,4] where the busbar metallization is decoupled from the contact finger metallization by an intermediate insulation layer. It is compatible with ribbon-or foil-based module integration technologies and consists of three consecutively screen-printed layers: the contact finger metallization, the insulation layer, and the busbar metallization.…”