To make silicon photovoltaic modules involves creating metal contacts on the surfaces of the individual solar cells, then connecting those cells in series to make modules. Since the 1970’s almost all commercially produced modules have been interconnected by soldering copper ribbons to the metal contact regions on the solar cells. But today, as gains in solar cell efficiency are more difficult to achieve, attention is increasingly moving to focus on new ways of interconnecting the cells into modules to increase their performance.  

Of particular interest are new module technologies that do not require high temperature soldering and can achieve high module areal efficiencies (e.g., by tiling the cells so there is no gap between them). Our research focuses on new lower temperature processes where the metal contacts of the solar cells can be bonded to the interconnection ribbons during the module encapsulation process. This can enable the interconnection of cells, such as silicon heterojunction cells, which are sensitive to the higher temperatures typically used for soldering. Our bonding methods rely on the use of low melting point solders which have the additional environmental benefit of eliminating the use of lead in modules. 

Our people

Postdoctoral fellows 

  • Pei-Chieh Hsiao 
  • Yang Li 
  • Ning Song 

PhD students 

  • Mreedula Mungra 
  • Mr Zhimeng Wang 
  • Research Assistant 
  • Mrs Carolin Roemer 

Industry partners 

LONGi Solar, China 

Yourbest New-Type Materials Co., Ltd



DSM Solar, Netherlands

ECN part of TNO, Netherlands 

Contact us  

Find more information on all the interesting projects we’re working on and request access to our materials 

Alison Lennon 

Research partnerships

If you’re interested in becoming a postgraduate research candidate at SPREE, please connect with us. We also welcome partnerships with industry and would love to talk to you.

Julie Lui (postgraduate enquiries) 

Bram Hoex (research partnerships)