介电储能用无铅铁电陶瓷介质的缺陷工程设计与高性能化协同构筑

高性能脉冲电容器因储能密度高、放电速度快及循环寿命长等特性已成为国防、航空航天和医疗等领域发展不可或缺的脉冲电源的关键性部件，然而其严重受限于电介质材料，难以实现高储能密度与长循环寿命的兼顾。本项目基于无铅弛豫反铁电陶瓷介质材料在强电场下的优异表现，利用缺陷工程调控NBT-AN无铅弛豫反铁电体系，揭示其极化耦合机制，避免极化失配，建立缺陷工程调控模式与储能特性间定量模型，从而研制性能优异的无铅弛豫反铁电陶瓷组分；同时拓展铁电粉体制备技术，提升无铅弛豫反铁电体本征特性；借助轧膜技术构筑无铅铁电陶瓷介质层（如NBT-AN, NBT基，AN基介质层），研究无铅陶瓷介质层间的协同关联作用，阐明复合叠层协同耦合影响电容器宏观性能的物理机制，最终突破高性能片式脉冲电容器的关键基础技术。

Because of the characteristics of high energy storage density, fast discharge speed and long cycle life, high-performance pulse capacitors have become an indispensable key component in the development of national defense, aerospace, medical and other fields. However, they are seriously limited by the basic dielectric materials, making it very difficult to achieve a combination of high energy storage density and long cycle life. Based on the excellent characteristics of lead-free relaxor antiferroelectric ceramics under a strong electric field, this project uses defect engineering to control the doping behaviors in NBT-AN system, reveals polarization coupling mechanism, avoids polarization mismatch, and establishes quantitative relationship model between doping amount and energy storage characteristics, in order to develop lead-free relaxor antiferroelectric ceramics with excellent performance. Meanwhile, this project will expand the preparation technology of ferroelectric powder and improve the intrinsic characteristics of lead-free relaxor antiferroelectrics. Also this project will build lead-free ceramic dielectric layers (such as NBT-AN, NBT-based, AN-based) using a viscous polymer process, study the synergistic coupling between the dielectric layers of lead-free ceramics, clarify the physical mechanism of collaborative coupling of laminated composites affecting the macro performance of capacitors, and finally leading to the breakthrough of the key basic technology of high-performance multi-layer pulse capacitors.