Gradient‐Structured Ceramics with High Energy Storage Performance and Excellent Stability
Fei Yan, Guanglong Ge, Jin Qian, Jinfeng Lin, Chukai Chen, Zhifu Liu, Jiwei Zhai
Abstract
Abstract Owing to the high power density, eco‐friendly, and outstanding stability, the lead‐free ceramics have attracted great interest in the fields of pulsed power systems. Nevertheless, the low energy storage density of such ceramics is undoubtedly a severe problem in practical applications. To overcome this limitation, the lead‐free ceramics with gradient structures are designed and fabricated using the tape‐casting method herein. By optimizing the composition and distribution of the gradient‐structured ceramics, the energy storage density, and efficiency can be improved simultaneously. Under a moderate electric field of 320 kV cm −1 , the value of recoverable energy storage density ( W rec ) is higher than 4 J cm −3 , and the energy storage efficiency (η) is of ≥88% for 20‐5‐20 and 20‐10‐20. Furthermore, the gradient‐structured ceramics of 20‐10‐0‐10‐20 and 20‐15‐0‐15‐20 possess high applied electric field, large maximum polarization, and small remnant polarization, which give rise to ultrahigh W rec and η on the order of ≈6.5 J cm −3 and 89–90%, respectively. In addition, the energy storage density and efficiency also exhibit excellent stability over a broad range of frequencies, temperatures, and cycling numbers. This work provides an effective strategy for improving the energy storage capability of eco‐friendly ceramics.