Half-cells are another popular module technology advancement that has been adopted by many manufacturers. The process involves cutting (cleaving) a processed cell in half and is based on the logic that the two halves will produce the same voltage output but half the current. Based on the relationship, Ploss = I2R, with half the current flowing within each cell, the electrical resistive losses are reduced by 75%. Half-cell modules must therefore, also be split in half where the resulting module looks like 2 smaller, square modules connected in parallel. The International Technology Roadmap for Photovoltaics (ITRPV) predicts that half-cells, with a current market share of 5% will gain ~40% by 2029.
To implement this technology in the manufacturing line, stringer and tabbing equipment must be doubled and new lasers for cleaving are required. Investing in the new equipment will allow manufacturers to maintain the same production capacity of traditional module manufacturing. However, with an easy boost of about 5 to 6 W with this implementation alone, it makes a lot of sense. Many leading manufacturers are producing these modules with some companies completely transitioning to half-cell modules only. The technique results in traditional 60 and 72 cell panels containing 120 and 144 half-cells respectively. Since they can be housed in the same size module as their whole-cell counterpart, the increase in power output per area leads to a clear cell-to-module gain.
Furthermore, half-cells are often combined with a number of advanced PV module designs including, multibusbar, bifacial, larger wafer formats and even paving. Jinko Solar’s SWAN is one example, boasting 435 W power output from front illumination alone [3]. The 435 W SWAN module features half cells, 5 busbars, bifacial and a cell side length 158.75 mm. It also uses a clear tedlar backsheet developed by DuPont for a lighter bifacial design.
