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The discharge performance of antiferroelectric (AFE) capacitors is complicated and difficult to simulate due to the nonlinear polarization behavior of AFE. In this work, a nonlinear model for pulsed discharge AFEs was proposed based on a combination of the Preisach model and Kirchhoff's law. The model was driven by the data from first-order reversal curves and direct-current-bias (DC-bias) dielectric test measurements. Thus, the discharge behavior of the AFE can be studied without actual discharge experiments. Specifically, AFE discharge waveforms were calculated and evaluated for different size parameters and external circuit parameters that were conducive to compare the properties of different AFE materials. Moreover, the size effect of the capacitor on the discharge performance was discussed, which should draw the attention of researchers to prevent exaggerated conclusions. As a consequence, this method would fill the gap of AFE discharge simulation. [ABSTRACT FROM AUTHOR]

The capacitors are in rising demand for cryogenic applications. As for now, it still remains an ongoing challenge for simultaneously achieving high energy storage density and cryogenic temperature stability. Herein, the strategy of stable backward phase transition was demonstrated in the antiferroelectric composition of (Pb0.9175La0.055)(Zr0.975Ti0.025)O3. As a result, we achieved high recoverable energy density about 10 J/cm3 with exceptional low-temperature stability from −160 to 25 °C. Multi-layer ceramic capacitors designed for pulse discharge applications also demonstrated high performance in cryogenic conditions, with the peak current fluctuations of less than 4%. Through in situ characterizations using x-ray diffraction, Raman spectra, and transmission electron microscopy, we discovered that the anisotropic structural evolution is responsible for a stable backward phase transition, providing the material with robust stability at cryogenic temperatures. These results offer a good paradigm for improving the temperature stability of antiferroelectric multi-layer capacitors to meet the rigorous demands of energy storage applications. [ABSTRACT FROM AUTHOR]

In the practical application of capacitors, especially in pulsed application, recoverable energy is a key parameter, which represents the ability to store energy. However, many existing evaluation methods for energy storage calculation have not been systematically implemented and comprehensively understood. In this work, four methods were applied to calculate the energy storage in linear, ferroelectric, and antiferroelectric capacitors. All methods were valid when the linear capacitor was examined. In terms of the ferroelectric capacitor, the method of equivalent parameter using DC-bias capacitance was infeasible under the high voltage owing to a massive decrease in field-dependent capacitance. As for the antiferroelectric capacitor with noticeable hysteresis, the maximum of energy storage was obtained by the method of integration of hysteresis loop, while the lower one was obtained in the fast discharge condition by the method of integration of UI (product of voltage and current). In summary, for different materials, both test conditions and calculation methods should be considered to get accurate energy storage, which best fits the working conditions. [ABSTRACT FROM AUTHOR]