太阳电池有无减反射膜的短路光电流增量比上限

太阳电池覆盖各种减反射膜或作其它减反射表面处理后,其短路乐电流密度的增量与有减反射膜的短路光电流的比ΔＪＬ／ＪＬ小于或等于裸太阳电池表面加权平均反射率Ｒｗ,即ΔＪＬ／ＪＬ〈Ｒｗ。     

AlxGa1-xAs/GaAs太阳电池MgF2/ZnS双层减反射膜的研究

介绍了在AlxGa1-xAs/GaAs太阳电池上制备MgF2/ZnS双层减反射膜的研究工作,引入了有效反射率R,并通过使Re极小来实现减反射膜的优化设计,考虑了MgF2/ZnS双层减反射膜与窗口层的耦合,实验上获得了良好的减反射膜,提高了AlxGa1-xAs/GaAs太阳电池的短路电流和效率,表明用Re极小化来设计减反射膜是合理的。     

宽角度硅太阳电池减反射膜的优化设计

以太阳电池减反射膜为研究对象,考虑太阳光从O°～60°宽角度人射,同时结合硅的光谱响应和太阳光谱分布,采用加权平均反射率作为评价膜系质量的标准,利用数值计算设计了的最佳双层减反射膜SiNx/SiOxo计算结果表明30°是设计减反射膜的最佳优化角度.对于入射介质为空气时,最优薄膜参数为nSiNx=2.3,dSiNx=56nm,nSiO2=1.46,dSiO2=90nm.当太阳电池封装后,即入射介质为硅胶时,最佳膜系参数为nSiNx=2.3,dSiNx=65nm,nSiOx=1.63nm,dSiO=80nm.     

固定式光伏方阵日照性能

照射到太阳电池表面的太阳光的入射角随时间而变化，导致电池表面减反射膜系的反射率随时间发生变化，使太阳电池对太阳能的吸收产生了影响。该文从地球绕太阳运动的基本规律出发，设计出了实用的计算机软件，对固定式光伏方阵的减反射膜系统进行了分析，比较了在改变减反射膜参数的情况下，光伏方阵对太阳能的利用情况，对光伏方阵的设计具有一定的指导意义。     

双层氮化硅薄膜对晶硅太阳电池性能的影响

利用管式PECVD在晶硅太阳电池上制备3种不同结构的Si Nx∶H减反射膜:第一子层(靠近基底硅)折射率大于第二子层的双层减反射膜、第一子层折射率小于第二子层的双层减反射膜、单层减反射膜。通过光学和电学性能的比较可看出,第一种类型太阳电池的短路电流、开路电压和电池效率的分布区间均相对集中,其短路电流和开路电压均高于其他样品。该结果主要归结于该类型双层Si Nx∶H减反射膜不但光学匹配性好,而且对太阳电池的表面及体钝化效果最优。     

多结太阳电池减反射膜的优化

基于多层膜的光学计算基本原理,模拟分析多结化合物太阳电池减反射膜的反射谱。模拟结果准确的反应了实际测量结果。以此为基础设计优化Ti O_x/Al_2O_3/MgF_2三层减反射膜,在GaInP/In_(0.01)GaAs/Ge三结太阳电池上实现了减反射膜对子电池响应电流的精确调节,并得到了子电池电流匹配的GaInP/In_(0.01)GaAs/Ge太阳电池,短路电流密度相比制备减反射膜前提升35.84%。     

AlxGa1—xAs／GaAs太阳电池减反射膜的研究

以太阳电池的短路电流积分表达式为依据，应用减反射膜的光学原理，对具有阳极氧化、ＳｉＯ和ＳｉＯ２三种减反射膜的ＡｌｘＧａ１－２Ａｓ／ＧａＡｓ太阳电池分别进行了反射光谱、短路电流、开路电压的实验测试。研究表明，阳极氧化膜、ＳｉＯ膜具有良好的减反射性能，而ＳｉＯ２膜的减反射性能较差。     

等离子体增强CVD氮化硅作硅太阳电池的减反射膜

本文报道了用等离子体增强化学气相淀积(简称PECVD)氮化硅作硅太阳电池减反射膜的实验结果。利用红外吸收光谱、俄歇电子能谱、椭圆偏振仪及C—V测试等分析方法研究了氮化硅膜的成份和性能。利用氮化硅膜的折射率随淀积工艺可变这一特点,淀积了具有不同折射率的多层氮化硅膜。实验表明,采用PECVD氮化硅膜作硅太阳电池的减反射膜,电池转换效率提高了38％,四层氮化硅减反射膜的平均反射率低于5％(波长范围400—1100nm)。     

适用于GaAs多结太阳电池的宽光谱Al_2O_3/SiO_2/Nano-SiO_23层减反射膜的研制

减反射膜在太阳电池应用中非常重要,然而传统的双层镀膜减反射膜已无法满足GaAs电池的拓展需要。因此,本研究在之前双层镀膜的基础上进行新薄膜结构的设计优化。使用溶胶-凝胶法制备出新结构的3层减反射膜。通过XRD对薄膜晶体结构进行分析,使用椭偏仪对薄膜折射率和物理厚度进行测试,使用分光光度计对减反射膜减反射效果进行验证。通过对3层减反射膜的折射率和物理厚度进行优化,成功在无窗口层的GaAs衬底上制备出350~1800nm波段平均反射率为10.34%的3层减反射膜。     

大面积高效率空间用三结砷化镓太阳电池的研究

通过在电池中引入布拉格反射器,提高电池抗带电子辐照能力,经辐照后使电池最大功率平均衰减小于18%。优化上电极栅线结构,当金属栅线面积占电池面积的3.0%时,电池平均短路电流为456.2mA。优化TiO_x/AlO_x双层减反射膜结构,短波300~500nm范围内电池表面反射率小于30%。采用以上结构最终制备出面积为26.8cm~2的空间用三结砷化镓太阳电池,批产平均转换效率为29.61%,最大转换效率30.15%。     

High performance anti-reflection coatings for broadband multi-junction solar cells

The success of bandgap engineering has made high-efficiency broadband multi-junction solar cells possible with photo-response out to the band edge of germanium. Modeling has been conducted which suggests that current double-layer antireflection coating technology is not adequate for these devices in certain cases. Approaches for the development of higher performance antireflection coatings are examined. A new antireflection coating structure based on the use of Herpin equivalent layers is presented. Optical modeling of the new AR coating suggests a decrease in the solar weighted reflectance of 2.5% absolute over typically used double-layer antireflection coatings. This structure requires no additional optical material development and characterization because no new optical materials are necessary. Experimental results and a sensitivity analysis are presented.     

n型高效抗PID太阳电池工艺研究

电势诱导衰减(PID)效应是导致光伏组件输出功率下降的主要原因之一,该文研究表明通过优化n型太阳电池工艺,包括增加p-n结的深度,提高减反射膜的折射率,采用叠层减反射膜等方式,可阻挡钠离子破坏太阳电池的p-n结,将太阳电池的PID衰减控制在1.5%以内。同时结合离子注入技术,太阳电池的量产效率可达到21.4%以上,形成了一套高效率高稳定性的太阳电池制备工艺。     

TiO_2/SiO_2双层减反膜在太阳电池上的应用

利用二氧化硅(SiO_2)对太阳电池表面的钝化作用,对传统的二氧化钛(TiO_2)单层减反膜进行了改良.基于理论模拟分析了光反射率随膜层(TiO_2/SiO_2)厚度变化规律,结合实验上SiO_2最佳厚度经验值,制备了晶体硅太阳电池(即TiO_2/SiO_2/Si),并和SiN_x/Si结构的晶体硅太阳电池相比较.分别测试了少子寿命、反射率、电性能参数等,结果表明这种改良后的TiO_2减反膜也可以取得很好的减反效果和钝化效果.镀有TiO_2,SiO_2双层膜与SiN_x减反膜绒面晶体硅片的积分反射率分别为4.9%和3.9%;使用以上两种不同减反膜制备的太阳电池的开路电压均可达到0.62V.可见这种TiO_2双层膜有望在将来的生产中得到具体应用.     

Investigations of solar cells with porous silicon as antireflection layer

The possibility of using porous silicon layers as antireflection coating instead of the antireflection coatings in common silicon solar cells was investigated. A technology for the manufacture of porous silicon antireflection layers was developed. The comparison of the photovoltaic and optical characteristics of investigated samples of solar cells with ZnS antireflection coating and with porous silicon antireflection coating is presented. It is shown that the formation of the porous layer under optimal technological regimes leads to significant improvement of the main photovoltaic parameters–short-circuit current and open-circuit voltage.     

Computations of the optical properties of metal/insulator-composites for solar selective absorbers

Solar selective absorbers are very useful for photo thermal energy conversion. The absorbers normally consist of thin films (mostly composite), sandwiched between the antireflection layer and (base layer on) a metallic substrate, selectively absorbing in the solar spectrum and reflecting in the thermal spectrum. The optical performance of the absorbers depends on the thin film design, thickness, surface roughness and optical constants of the constituents. The reflectivity of the underlying metal and porosity of the antireflection coating plays important roles in the selectivity behavior of the coatings. Computer simulations, applying effective medium theories, have been used to investigate the simplest possible design for composite solar selective coatings. A very high solar absorption is achieved when the coating has a non-uniform composition in the sense that the refractive index is highest closest to the metal substrate and then gradually decreases towards the air interface. The destructive interference created in the visible spectrum has increased the solar absorption to 98%. This paper also addresses the optical performance of several metals/dielectric composites like Sm, Ru, Tm, Ti, Re, W, V, Tb, Er in alumina or quartz on the basis of their refractive indices. The antireflection coating porosity and surface roughness has been analyzed to achieve maximum solar absorption without increasing the thermal emittance. Antireflection layer porosity is a function of dielectric refractive index and has nominal effect on the performance of the coating. While, up to the roughness of 1×10⁻⁷ m RMS, the solar absorption increases and for higher roughness, the thermal emittance increases only.     

Screen printed titanium oxide and PECVD silicon nitride as antireflection coating on silicon solar cells

Silicon nitride and titanium oxide coatings have been used to reduce the reflection losses from silicon solar cells. Both 100-mm-diameter circular and 100 × 100 mm pseudo-square single crystalline silicon solar cells have been used in the present studies. More than 27% enhancement in the short circuit current has been demonstrated in polished cells using screen printed titanium oxide antireflection coating. Solar cells made from textured silicon wafers were used for plasma enhanced CVD grown silicon nitride antireflection coating on them. In these cells more than 23% enhancement in short-circuit current has been observed after silicon nitride antireflection coating.     

Plasma-enhanced CVD silicon nitride antireflection coatings for solar cells

Multilayer plasma-enhanced chemical vapor deposition (PECVD) silicon nitride antireflection coatings were deposited on space quality silicon solar cells. Preliminary experiments indicated that multilayer coatings decreased the total reflectance of polished silicon from 35 per cent to less than 3 per cent over the spectral range 0.4–1.0 μm. The solar cell energy conversion efficiency was increased from an average of 8.84 per cent to an average of 12.63 per cent.     

On the stability of optical properties of antireflection coatings for solar cells based on a silicon-silicon-oxide mixture

It is investigated how the storage duration influences the optical properties of antireflection coatings based on silicon-silicon-oxide mixture intended for silicon solar cells. It is shown that the spectral reflection coefficient changes by 2.7% for 22 years; i.e., the antireflection effect is retained. We draw the conclusion that coatings based on silicon-silicon-oxide mixture can greatly increase the lifetime of solar cells and a solar battery.     

Antireflection coatings for solar elements based on a composition of Ge and GeO2

The optical properties of a single layer antireflection coating for solar elements based on a composition of Ge and GeO₂ are studied. The results of computer modeling and optical measurements led to the conclusion that a single layer coating based on a composition of Ge and GeO₂ is an efficient antireflection coating and has technological advantages as compared with the traditionally used coatings.