导热PET绝缘背板对光伏组件发电效率的影响

Effect of Thermal Conductive PET Insulation Backsheet on Generating Efficiency of Photovoltaic Module

提高光伏背板的导热系数可使光伏组件产生的热量扩散到空气中,降低工作温度,使发电效率提升,还可延长使用寿命,减少热斑,降低组件失配的发生。通过沉淀法合成纳米级片状氧化铝,采用X射线衍射(XRD)、扫描电镜(SEM)和傅里叶变换红外光谱(FTIR)对片状氧化铝进行表征。然后将其在PET切片合成过程中进行原位分散,采用超声辅助最大程度减少片状氧化铝的团聚,再将导热PET切片进行铸片-双向拉伸成膜。结果表明:所得氧化铝粉末具有明显的片状结构,粒径分散均匀。纳米片状氧化铝的加入对薄膜性能没有劣化影响,可作为太阳能背板绝缘用基膜。氧化铝导热网络的形成使PET薄膜的导热系数由0.22 W/(m·K)提高至0.91 W/(m·K),可使组件工作温度降低5℃以上。

Increasing the thermal conductivity of photovoltaic backsheet can not only spread heat to air and improve generating efficiency, but also extend lifetime and decrease hot-spot and module mismatch. In this paper, a nano-Al_2O_3 sheet was synthetized through precipitation method, and it was characterized by XRD, SEM and FTIR. The nano-Al_2O_3 sheet was dispersed in synthesis process of PET chip through ultrasonic dispersion method to decrease the aggregation, and the thermal conductive PET chip was biaxi- al stretched to prepare BOPET film. The results show that the nano-Al_2O_3 powder has obvious sheet struc- ture and the particle sizes distribute uniformly. The introduction of nano-Al_2O_3 sheet has no degradation effect on the properties of PET film, which can be used as basement membrane of solar cell backsheet. The formation of nano-Al_2O_3 thermal conductive network make the thermal conductivity of PET film increase from 0.22 W/（m· K） to 0.91 W/（m· K）, which decreases the work temperature of solar cell over 5℃.