- 學位論文
利用逐步應力試驗法分析III-V三接面太陽能電池衰退機制
Degradation Mechanism of III-V Triple Junction Solar Cells Analyzed Using Step Stress Tests
摘要
對於聚光型太陽能電池而言，加速衰退試驗(Accelerated Degradation Test；ADT)是一項重要的試驗方法。ADT有兩種方法：固定應力(Constant Stress)加速衰退試驗(CSADT)和逐步應力(Step Stress)加速衰退試驗(SSADT)。 本實驗主要是針對未塗佈光學膠的III-V族化合物聚光型InGaP/InGaAs/Ge太陽能電池進行逐步應力加速衰退試驗(SSADT)，探討其衰退機制及成因。實驗溫度分別為90、110、130和150℃，累積時數為25、55、85和135小時。 經過本實驗，可得知GaInP/GaInAs/Ge太陽能電池經過SSADT後，暗電流-電壓曲線的變化明顯看出邊緣復合電流的增加，另一方面藉由光電流-電壓曲線得知開路電壓與填充因子呈現逐步下降的現象。以上趨勢與電池的效率變化皆呈現正相關的特性。
並列摘要
Accelerated degradation test (ADT) is an essential tool to demonstrate reliability of concentration solar cells. There are two methods of accelerated degradation test：constant stress accelerated degradation test (CSADT) and step stress accelerated degradation test (SSADT). The purpose of this study is to examine the degradation mechanism of GaInP/GaInAs/Ge solar cells. We analyzed the degradation mechanism of GaInP/GaInAs/Ge triple junction solar cells without coating any protective film. Gradual degradation in the dark and light I-V characteristics of the solar cells were observed after the step stress accelerated degradation tests (SSADT) were conducted on these devices sequentially at 90, 110, 130 and 150℃for 25, 55, 85 and 135 hours, respectively. The recombination current in the depletion region at the chip perimeter of solar cells, resulting in the decrease of open-circuit voltage (VOC), fill factor (FF) and efficiency, is suggested to be the important degradation mechanism for GaInP/GaInAs/Ge triple junction solar cells.