Thermal-mechanical-electrical coupled design of multilayer energy storage ceramic capacitors

A combination of two-dimensional (2D) and three-dimensional (3D) finite element (FE) models of large size multilayer energy storage ceramic capacitors (MLESCCs) was established to simulate the distribution of internal electric field (IEF) under an applied electric bias after sintering process. The sintering stress calculated through thermal-mechanical-coupling was taken as the initial value for mechanical-electrical-coupling under an applied electric bias. The effect of geometric parameters, namely margin length, the gap between two internal electrodes, the thickness of covered layer and the internal electrode fillet radius, on distribution of electric field was studied. Numerical results indicate that the initial stress caused by sintering process would aggravate the non-uniformity of IEF but the adjustment of geometric parameters could improve such non-uniformity, which can serve as reference to the design of MLESCCs. A standard three-factor three-level full factorial design was introduced to pursue a more reasonable design ensuring both large capacitor and high-breakdown voltage