Study On Preparation Technology And Performance Of Double Glass Shingled Cells Module

Shingled cells module is the development trend for photovoltaic(PV)modules technology in the several years to come.However,the shingled technique is not mature enough and the reliability of the shingled cells module remains to be proved.In this paper,aiming at the different preparation technics between conventional PV module and shingled cells PV module,we investigated the effect of laser cutting technology parameters by analysis of the cutting loss and the cut structure.We determined the selection of conductive adhesive by analysis of the electrical and mechanical properties and the feasibility for process matching.We invested the effect of electrical connection structure on the reliability of PV modules by contrastive analysis of the thermal cycling aging properties between copper ribbon soldering and conductive adhesive bonding.We investigated the electrical performance gain and the reliability of the shingled cells module by electrical tests,thermal cycling aging tests and heat-humidity ageing tests.Lastly,we improved circuit configuration by shading tests.The main results of our researches were shown as follows:(1)As the laser power increasing,the cutting loss changed small at the beginning,stabilized around 2.1%,but increased rapidly to 3.39%after the damage of PN junction.As the cutting times increasing,the breaking loss gradually increased while the scribing loss decreased.Combining the two losses,the cutting loss of 1.72%was smallest under cutting 2 times.(2)The resistance of the conductive adhesive decreased quickly first followed by insignificant change with the increase of curing time.After curing,the organic vehicle changed to be network.For organosilicone conductive adhesives,it remained good flexibility.However,for acrylate conductive adhesives,it solidified to be hardened thereby making the rework difficult.Organosilicone conductive adhesive is the optimal choice for shingled cells module.(3)The mismatch of thermal expansion coefficients of the various soldering interconnection materials produced thermal stress,leading to the connection failure at the end soldering track.(4)Comparing with the conventional module,the shingled cells module can produce 7%-8%maximum power gain.However,the reliability of the shingled cells module is yet to be improved under thermal cycling aging and damp-heat aging.200 thermal cycles aging leaded to 6.2%maximum power loss.400h damp-heat aging leaded to 5.85%maximum power loss.(5)The shading loss can be reduced by reforming circuit configuration.It can mitigate the hotspots damage and enhance the power output by incorpating more bypass diodes in the shingled cells module.