平板式固態氧化物燃料電池（SOFC）具有較簡單的結構設計與製作成本、較高能源效率、較低工作溫度（800oC以下）等優點，為目前全世界對SOFC研發的重點。為配合核能研究所開發平板式固態氧化物燃料電池（SOFC）發電系統，本計畫將進行平板式SOFC電池堆組件機械強度測試及劣化機制分析，並進一步發展電池堆結構耐久壽命評估模式。SOFC系統在運轉使用時，隨著工作溫度的改變，由於不同組件間具有不同的熱膨脹係數值，加上工作環境溫度分佈不均勻，因而會產生不可忽視的熱應力。對陶瓷材料所製成的三合一電池片（PEN）及電池堆封裝用之玻璃陶瓷而言，熱應力可以促進陶瓷材料既存孔隙或缺陷成長為較大的裂縫造成組件的洩漏或破損，降低電池的效率，因此對SOFC電池堆進行熱應力分析與耐久機械強度評估，將是設計SOFC系統不可或缺的步驟。依此，本計畫本年度將配合有限元素數值模擬分析所獲致之SOFC電池堆熱應力分佈數據，對核能研究所所開發之電池片及封裝玻璃陶瓷與金屬連接板接合件進行在工作溫度下受該等熱應力作用之高溫機械強度試驗，並分析其機械強度劣化機制，進而建立平板式SOFC電池堆耐久壽命評估最佳化模式，作為核能研究所設計平板式SOFC電池堆結構與組件材料選擇的參考依據。 ; As planar solid oxide fuel cell (SOFC) systems have several advantages such as compact size, higher energy efficiency and lower operating temperature (below 800oC), most of the current development of SOFC is being focused on the planar type. The typical materials used for anode, electrolyte, and cathode (often called a positive electrode-electrolyte-negative electrode, PEN) in SOFCs are all ceramic materials and brittle in mechanical characteristics. In addition, glass ceramics are also being used as a sealant material in planar SOFC stacks. The high-temperature operation, however, gives rise to significant thermal stresses caused from mismatch of coefficients of thermal expansion among various components and temperature gradients in the SOFC system. When a ceramic component is held under such a prolonged thermal load (stress), pre-existent pores or defects which are subcritical, i.e. less than the critical defect size for immediate failure, can grow to failure and degrade the performance of a SOFC system during service. The purpose of this proposal is to characterize the thermal stress distribution in a planar SOFC system which is being developed at the Institute of Nuclear Energy Research (INER). It is also intended to establish a mechanical testing technique and determine the high-temperature mechanical properties of the ceramic components and the glass ceramic-metallic interconnect joints used in this developing planar SOFC system. A 3-D finite element model for a multiple-cell SOFC stack will be constructed to solve the thermal stress distribution in different stages including start-up and steady operation. In addition, mechanical testing of the high-temperature strength and durability of the PEN and the glass ceramic-metallic interconnect joint will be conducted in conjunction with numerical analysis for assessment of the risks related to operation of the SOFC stack when subjected to the thermal stresses. Based on the numerical and experimental results, an optimal design and life assessment model for planar SOFC systems will be developed and applied to the planar SOFC system being developed at INER. ; 研究期間 9801 ~ 9812
