Nanoelectronics research institute imec and BE Semiconductor Industries N.V. (Besi), a manufacturer of assembly equipment for the semiconductor industry, say they have demonstrated long-term reliability in five full-size 60-cell nickel/copper/silver (Ni/Cu/Ag)-plated solar cell modules.
According to the partners, the modules consist of 60 front-side laser ablated and Ni-Cu-Ag-plated p-type Cz-Si cells. The plating was performed with Meco’s Direct Plating Line, an industrial plating tool, followed by annealing in an inline belt furnace. Cells were interconnected using standard soldering and lamination processes.
The partners say two of the five modules were subjected to 600 thermal cycles (-40°C to +85°C), and they passed this three times IEC61215 specification, with overall power losses of only 1.5% and 1.8%. One of the modules was subjected to a 1000h damp-heat test (85°C, 85% RH) with no power loss (0.1% gain), and two of the modules were submitted to a serial testing of 15 kWh UV-conditioning followed by 50 cycles temperature cycling followed by 10 cycles humidity-freeze-test, after which they showed overall power losses of only 0.5% and 3.0%.
The partners claim these test results prove the long-term reliability potential of imec’s and Besi’s Cu-plated cells and modules, as they have now outperformed the industrial standard for reliability, which requires less than 5.0% loss relative to initial power.
“We are very pleased with this result,” states Richard Russell, principal engineer at imec. “It demonstrates our industrial leading knowledge on how to make reliable Ni/Cu/Ag-plated solar cells and modules with a low-cost industrial manufacturing process.”
“After the excellent result of the 600 thermal cycle test earlier this year on one module, we are delighted to confirm that these results can be repeated on a larger set of five modules,” adds Martijn Zwegers, solar product manager at Besi. “Furthermore, it indicates that modules with Cu-plated cells lead to industry-standard reliability, paving the way for Ni/Cu/Ag-plated cells as a viable, low-cost alternative to front-side screen printing of Ag pastes.”
Figure courtesy of imec: Change in maximum power output for three modules during thermal cycling (-40°C to +85°C).