From Half-Cut to Third-Cut and Quarter-Cut: The Finer the Cell Is Sliced, the Harder Field EL Has to Work

ⓘ This article is currently published in Chinese. An English version is being prepared — read the Chinese original.

Multi-cut cell architecture has moved from an option to a default in the Chinese module market. Industry reporting puts multi-cut penetration at roughly 3-6% in 2025, passing 15% in the first half of 2026, and new multi-cut product lines keep coming off the line - QSUN rolled out its multi-cut modules at the Dongtai base on 9 October 2026. The physics behind the shift is simple: cutting a cell into three reduces its operating current to one third, and resistive loss falls with the square of current, to one ninth. Published figures place a full G12 cell around 18 A, half-cut around 9 A, third-cut around 6 A and quarter-cut around 4.5 A. What is less discussed is what this does to inspection. This article looks at multi-cut modules from the asset owner's side rather than the cell manufacturer's side, and argues that three things change at once in an electroluminescence image. First, spatial sampling: each cell unit now occupies a smaller area, so the same camera at the same working distance puts fewer pixels on each unit, and a crack that was readable on a half-cut module can fall below the readable threshold on a quarter-cut one. Second, cut edges: every additional slice adds another laser-processed edge, and edge micro-damage is a structural feature of the architecture rather than an anomaly, which makes edge-line darkening easy to confuse with transport-induced cracking. Third, interconnection: more sub-strings, more solder or adhesive joints, and a more complex bypass-diode topology, so a dark band in EL must first be classified as a circuit effect or a cell effect before anything else is concluded. The article also covers current injection for higher-voltage multi-cut modules, what to specify in an incoming-inspection or acceptance document, and how to keep defect-counting rules consistent when one physical crack can span several cell units.