Series Connection Front-To-Front And Back-To-Back Of Silicon Heterojunction Solar Cells

Alternating cells with p-and n-type emitters enables direct series connection of equivalent sides, i.e. front-to-front and back-to-back connection of adjacent cells. The challenge is to match the current of cells with p-and n-type emitters. The electrical properties of silicon heterojunction solar cells with front and rear junctions are remarkably similar. The short-circuit current density mismatch between front and rear junction cells is as low as 0.1 mAcm(-2). The cells are connected using thin indium coated wires. One-cell and two-cells modules were manufactured, and efficiencies up to 21.2% were reached for one-cell modules. Electroluminescence of the two-cells module is a good indication about the quality of the direct series connection between front and rear junction cells.