染料敏化太陽能電池的電解液是影響個電池效率相當重要的一個角色，我們針對不同溶劑系統所組成的染料敏化太陽能電池進行一系列溫度加速衰變的實驗，包含”有機溶劑MPN系統”、”高分子溶液PEGDME系統”以及”離子溶液EMITCB系統”，並建構其衰變模型，衰變模型中包含了一個對數線性的衰變路徑，誤差項則考慮了樣本與樣本間的變異以及隨著Wiener過程與時間有相關性的漂移誤差。利用溫度條件而得到的衰變模型，我們再透過阿瑞尼斯關係式將不同溫度下的衰變模型結合，如此得到的加速衰變模型可以用來預測任意加速溫度以及任何時間下的衰變情形。
由加速衰變實驗以及加速衰變模型的結果中，我們都可以發現以MPN系統的太陽能電池雖然有較高的初始效率，但隨著時間增加，會出現快速的衰變且不穩定；PEGDME系統的太陽能電池衰變的速度較為緩慢，樣本間也比較穩定，但初始效率不高；EMITCB系統太陽能電池是這三個系統中最為優異的，不僅在長期測試下衰變的速度極為緩慢，穩定度高，誤差程度小，加上EMITCB系統太陽能電池本身初始效率也不會比有機溶劑系統差太多，所以離子溶液是最適合用來製作太陽能電池之電解液的溶劑。
利用我們建立出來的加速衰變模型可預測出EMITCB系統太陽能電池在室溫下的保值期限，如果將光電轉換效率比率的殘餘值設定在90％，使用EMITCB的太陽能電池的平均保質期限推測約為8900小時，以95.4%的信賴區間考量下期限約為2900小時，將效率比率的殘餘值設定在80％時，平均保質期限推測約為18800小時，以95.4％的信賴區間考量下約為8500小時。

The electrolyte is an important component and its properties have much effect on the conversion efficiency and stability of DSSCs. In this study, a protocol for shelf-life estimating was proposed. Accelerated degradation tests were performed at several elevated temperatures. The results were analyzed using the degradation model for the log ratio of efficiencies at different times to the initial efficiency. The model includes a log-linear degradation rate which may vary from unit-to-unit due to common-cause variations in assembly, and a Wiener stochastic process which account for random-walk effects between measurements. An Arrhenius-type acceleration factor was used to describe effects of temperature, which allows us to extrapolate and predict degradation cells efficiency at an ambient temperature. The procedure was demonstrated using three types of dye-sensitized solar cells: one using a volatile organic solvent 3-methoxy-propionitrile, one using a nonvolatile organic solvent polyethylene-glycol-dimethyl-ether, and one using an ionic liquid 1-ethyl-3-methyl- imidazolium tetra-cyanoborate.
It is obvious that MPN-based DSSC shows the best efficiency among the three different system, but it also exists the fastest degradation, especially at elevated temperature. The PEGDME-based DSSC have slower degradation rates, but their initial efficiencies are low. The EMITCB-based have the slowest degradation rates, while their initial efficiencies are comparable to the MPN-based DSSC. The EMITCB-based electrolyte is the best and the most suitable one of these three different types of system.
Use of ionic liquid not only reduces the mean degradation rate but also the unit-to-unit variations. If a residual efficiency limit of 90% was used, the mean shelf-life of cells using ionic liquid was predicted to be about 8900 hours, with 95.4% confidence limit that it is greater than 2900 hours. If a residual efficiency limit of 80% was used, the mean shelf-life of cells using ionic liquid was predicted to be about 18800 hours, with 95.4% confidence limit that it is greater than 8500 hours.

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