Abstract A novel compressive boron nitride (h-BN) based seal has been developed for planar intermediate temperature solid oxide fuel cell (SOFC). It exhibited extremely low leakage rates and thermal cycling stability under simulated stack conditions. The h-BN based seal showed leakage rates of 0.01 sccm/cm under gas pressure of 6.8 kPa in the temperature range of 650–800 °C, and maintained similar leakage rates during 10 thermal cycles. The excellent sealing performance can be explained by oxidation of h-BN surface to form liquid B 2 O 3 layers beyond the critical temperature of 700 °C. Two of compliant B 2 O 3 glass layers were observed on the surface of the h-BN to adjoin well cell and metallic interconnect. The sandwich structure with liquid B 2 O 3 layer on two sides of the h-BN seal could not only enhance interfacial adherence but also eliminate the gas leakage paths at SOFC operation temperature. The applicability of the h-BN based seal has also been verified by single cell test.

中文翻译：

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用于平面中温 SOFC 的新型压缩 h-BN 基密封件的开发

摘要 一种新型压缩氮化硼 (h-BN) 基密封件已开发用于平面中温固体氧化物燃料电池 (SOFC)。它在模拟堆栈条件下表现出极低的泄漏率和热循环稳定性。h-BN 基密封在 650-800 °C 的温度范围内在 6.8 kPa 的气压下显示出 0.01 sccm/cm 的泄漏率，并在 10 个热循环期间保持相似的泄漏率。优异的密封性能可以通过 h-BN 表面在超过 700 °C 的临界温度时氧化形成液态 B 2 O 3 层来解释。在 h-BN 的表面上观察到两个兼容的 B 2 O 3 玻璃层，以与阱电池和金属互连相邻。h-BN密封两侧具有液态B 2 O 3 层的夹层结构不仅可以增强界面粘附性，还可以消除SOFC工作温度下的气体泄漏路径。h-BN 基密封的适用性也已通过单电池测试得到验证。