提高选择性发射极太阳电池组件量子效率的研究
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摘要
太阳能光伏发电技术是各国大力发展的可再生能源技术之一。晶体硅太阳电池是光伏产业的主流,其发展方向仍是提高光电转换效率和降低生产成本。选择性发射极技术已被证明是有效提高太阳电池转化效率的方法之一,它可显著提高太阳电池的短波响应。太阳电池一般都必须通过胶封、层压等方式封装成平板式构造的太阳电池组件才投入使用。传统密封剂EVA因其中添加了抗紫外剂,在短波段光透射率下降,这大大减弱了选择性发射极太阳电池的优势。针对这一情况,研究可以替代密封剂EVA的高透光率封装材料成为一个迫切的课题。
本文首先采用磷硅玻璃激光掺杂的方法实现选择性发射极单晶硅太阳电池的制备。接着在构建选择性发射极太阳电池组件光学模型的基础上,引入分贝概念,用分贝表示光能量在组件各部分材料中的损耗大小,将太阳电池组件中各因素对入射能量的影响表示为简单的和差关系,并在此基础上给出太阳电池组件的外量子效率和内量子效率定义式,使研究太阳电池组件中各部分封装材料对其光电转换效率的影响更加方便。最后,根据密封剂EVA和silicone的光透射率测量数据,计算了两种密封剂在280nm到1200nm波段范围内的吸收损耗；使用光谱响应测试仪分别测量了密封剂EVA和silicone封装的单片电池片在封装前后的量子效率,计算了两种密封剂在短波段300nm至500nm处为选择性发射极电池组件带来的短路电流密度的衰减。经比较得出,选择性发射极太阳电池组件使用密封剂silicone封装可提高其短波响应,即提高了量子效率。其研究结果对太阳电池组件的设计和制造具有重要参考价值。
Photovoltaic power generation technology is one of the renewable energy technologies that various countries are vigorously exploiting. Crystalline silicon solar cell is the mainstream of PV industry, and the directions of its development still are improving conversion efficiency and reducing production costs. Selective emitter technology has proven to be an effective way to improve the conversion efficiency of cells, which can significantly improve the short wavelength response of cells. Solar cells usually have to be encapsulated into flat module to put into use by sealing with glue, lamination, etc. The transmittance of traditional encapsulation EVA drops in short wavelength because of adding anti-UV dose, which will greatly reduce the advantages of selective emitter solar cells. Therefore, it has been a pressing issue to study high transparent encapsulation materials to replace EVA.
In this paper, firstly we use phosphosilicate glass laser doping method to achieve selective emitter monocrystalline silicon solar cell preparation. Then, on the basis of constructing the optical model of encapsulated selective emitter solar cell PV module, the concept of decibel is introduced and with it we describe the losses of light energy in the component parts of module. The impacts of various factors in module towards the incident energy are expressed as a simple and linear relationship. The definitions of external quantum efficiency and internal quantum efficiency of module are proposed so as to make it more convenient to study the effects of each encapsulation material on transfer efficiency of the PV module. Finally, according to the measured optical transmittance of EVA and silicone in the range of 200nm to 1200nm, the absorption losses of the two encapsulation materials are calculated; The spectral responses before and after encapsulation of single cells using EVA or silicone are tested, and then we calculates the short circuit current density attenuation for selective emitter solar cell modules using different encapsulation respectively in short wavelength 300nm to 500nm. By comparison, it is concluded that, using silicone can improve blue response of selective emitter solar cell module. In another word, using silicone can improve the quantum efficiency of module. This result has an important reference value on the solar cell module design and manufacturing.
本文首先采用磷硅玻璃激光掺杂的方法实现选择性发射极单晶硅太阳电池的制备。接着在构建选择性发射极太阳电池组件光学模型的基础上,引入分贝概念,用分贝表示光能量在组件各部分材料中的损耗大小,将太阳电池组件中各因素对入射能量的影响表示为简单的和差关系,并在此基础上给出太阳电池组件的外量子效率和内量子效率定义式,使研究太阳电池组件中各部分封装材料对其光电转换效率的影响更加方便。最后,根据密封剂EVA和silicone的光透射率测量数据,计算了两种密封剂在280nm到1200nm波段范围内的吸收损耗；使用光谱响应测试仪分别测量了密封剂EVA和silicone封装的单片电池片在封装前后的量子效率,计算了两种密封剂在短波段300nm至500nm处为选择性发射极电池组件带来的短路电流密度的衰减。经比较得出,选择性发射极太阳电池组件使用密封剂silicone封装可提高其短波响应,即提高了量子效率。其研究结果对太阳电池组件的设计和制造具有重要参考价值。
Photovoltaic power generation technology is one of the renewable energy technologies that various countries are vigorously exploiting. Crystalline silicon solar cell is the mainstream of PV industry, and the directions of its development still are improving conversion efficiency and reducing production costs. Selective emitter technology has proven to be an effective way to improve the conversion efficiency of cells, which can significantly improve the short wavelength response of cells. Solar cells usually have to be encapsulated into flat module to put into use by sealing with glue, lamination, etc. The transmittance of traditional encapsulation EVA drops in short wavelength because of adding anti-UV dose, which will greatly reduce the advantages of selective emitter solar cells. Therefore, it has been a pressing issue to study high transparent encapsulation materials to replace EVA.
In this paper, firstly we use phosphosilicate glass laser doping method to achieve selective emitter monocrystalline silicon solar cell preparation. Then, on the basis of constructing the optical model of encapsulated selective emitter solar cell PV module, the concept of decibel is introduced and with it we describe the losses of light energy in the component parts of module. The impacts of various factors in module towards the incident energy are expressed as a simple and linear relationship. The definitions of external quantum efficiency and internal quantum efficiency of module are proposed so as to make it more convenient to study the effects of each encapsulation material on transfer efficiency of the PV module. Finally, according to the measured optical transmittance of EVA and silicone in the range of 200nm to 1200nm, the absorption losses of the two encapsulation materials are calculated; The spectral responses before and after encapsulation of single cells using EVA or silicone are tested, and then we calculates the short circuit current density attenuation for selective emitter solar cell modules using different encapsulation respectively in short wavelength 300nm to 500nm. By comparison, it is concluded that, using silicone can improve blue response of selective emitter solar cell module. In another word, using silicone can improve the quantum efficiency of module. This result has an important reference value on the solar cell module design and manufacturing.
引文
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[4]张松,孟凡英,汪建强,刘峰,李翔,黄建华.低成本选择性发射区太阳电池的制备和特性[J].上海交通大学学报,2011,45(6)：793-797
[5]刘广荣.高效太阳能电池研发情况[J].半导体信息,2009,03：26
[6]张松.高效率晶体硅太阳电池关键技术研究[D].上海：上海交通大学,2011
[7]吴正军.新型高效太阳电池的设计与性能研究[D].无锡：江南大学,2009
[8]邵燕瑛.太阳电池组件封装技术的探讨[J].能源工程,2008,3：33-34
[9]申明霞,李红香,何辉.光伏组件用密封剂研究进展[J].综述,2008,29(7)：29-32
[10]陈小青,申明霞.光伏组件EVA封装胶膜的老化研究进展[J].粘接,2010,12：65-68
[11]王祺,倪志春.太阳组件封装损失研究[C].第十一届中国光伏大会暨展览会会议论文集,2010：1089-1090
[12]李玲,廖华,刘祖明,杨祚宝.太阳电池组件封装工艺研究[J].太阳能,2007,7：25-27
[13]王响,沈辉,舒碧芬,孙建伟.太阳电池封装技术的现状与发展建议[J].新材料产业,2008,5：16-20
[14]胡培明.太阳能电池的发展与分析[D].上海：上海交通大学,2008
[15]M.A. Green. Silicon solar cells:advanced principles and practice[M]. Sydney: University of New South Wales,1995:3
[16]马跃,魏青竹,夏正月,杨雷,张高洁.工业化晶体硅太阳电池技术[J].自然杂志,2010,32(3)：161
[17]任丙彦,吴鑫,勾宪芳,孙秀菊,于建秀,褚世君,励旭东.背接触硅太阳电池研究进展[J].材料导报,2008,22(9)：101-102
[18]李海玲,王文静.晶体硅电池产业化高效技术分析[J].新材料产业,2011,3：1-32
[19]班群.低成本颗粒硅带上薄膜太阳电池关键技术的研究[D].广州：中山大学,2006
[20]J Zhao, A Wang, M A Green. High-efficiency PERL and PERT silicon solar cells on FZ and MCZ substrates [J]. Solar Energy Materials and Solar Cells,2001,65:429-435
[21]S Wenham. Buried-contact silicon solar cells [J]. Progress in PV,1993,1:3-10
[22]郭志球,胡芸菲,沈辉,刘正义.晶体硅太阳电池制备工艺进展[J].新能源及工艺,2005,3：22-23
[23]施敏.半导体器件物理与工艺[M].苏州：苏州大学出版,2002：310-314
[24]S.R.Wenham.应用光伏学[M].上海：上海交通大学,2008：28-35
[25]庾莉萍.提高太阳能电池效率的主要措施[J].电器工业,2009,12：50
[26]屈盛,陈庭金,刘祖明.太阳电池选择性发射极结构的研究[J].云南师范大学学报,2005,25(3)：21-24
[27]赵建华,王艾华,高鹏.选择性发射结晶体硅太阳电池的制备方法[P].中国专利,CN101101936.2008-01-09
[28]屈盛,刘祖明,廖华,陈庭金.选择性发射极太阳电池结构及其实现方法[J].技术交流,2004,8：43
[29]梁学勤.晶体硅太阳电池新工艺实验研究和理论分析[D].广州：中山大学,2010：20-24
[30]赵赞良.高效选择性发射极太阳电池的制备和研究[D].成都：电子科技大学,2010：42-43
[31]Kyeong-Yeon Cho, II-Hwan Kim, Dng-Joon Oh, Ji-Myung Shim. Improvements of Voc by selective emitter pattern optimization in screen printed crystalline Si solar cells [C]. Photovoltaic Specialists Conference (PVSC),2011 IEEE:1335-1338
[32]艾凡凡,张光春.氮化硅掩膜法制备选择性发射极晶体硅太阳电池[J].人工晶体学报,2009,38(2)：383-384
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