To meet the United Nations' sustainable development goal of affordable and clean energy, there has been a growing need for low-cost, green, and safe energy storage technologies. High-field and energy-density capacitors have gained substantial attention from academics and industry, particularly for power electronics, where they will play a key role in optimising the performance of management systems in electric vehicles. The key figure of merit, energy density (W_rec), for high-field applications has dramatically increased year-on-year from 2020 to 2024, as evidenced by over 250 papers, demonstrating ever larger W_rec values. This review briefly introduces the background and principles of high energy density ceramics, but its focus is to provide constructive and comprehensive insight into the evaluation of W_rec, E_max, ΔP, and η, and more importantly, the normalised metrics, W_rec/E_max and W_rec/ΔP in lead-free dielectric ceramics. We also present several optimisation strategies for materials modification and process innovation that have been recently proposed before providing perspectives for the further development of high-field and high-energy density capacitors.

中文翻译：

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高场和高能量密度电容器中无铅介电陶瓷的当前发展、优化策略和未来前景


为了实现联合国的可持续发展目标，即负担得起的清洁能源，对低成本、绿色和安全的储能技术的需求不断增长。高场和能量密度电容器已受到学术界和工业界的广泛关注，尤其是电力电子领域，它们将在优化电动汽车管理系统的性能方面发挥关键作用。从 2020 年到 2024 年，高场应用的关键品质因数能量密度 （W_rec） 同比急剧增加，超过 250 篇论文证明了这一点，表明 W_rec 值越来越大。本文简要介绍了高能量密度陶瓷的背景和原理，但其重点是为 W_rec、E_max、ΔP 和 η 的评估提供建设性和全面的见解，更重要的是，标准化指标 W_rec/E_max 和 W_rec/ΔP 的评估在无铅介电陶瓷中。我们还提出了最近提出的几种材料改性和工艺创新的优化策略，然后为高场和高能量密度电容器的进一步发展提供了前景。