Potassium-ion hybrid capacitors (PIHCs) are in principle advantageous over the traditional metal-ion hybrid capacitors (MIHCs) in terms of low cost, safety, and reliability, holding enormous potential for the massive market, yet they remain largely an uncharted field. Herein, we provide a comprehensive review of recent advances on PIHCs, including fundamental understanding, device configurations, and design rationale. Then, technical hurdles that essentially impede the development of PIHCs are discussed, accompanied by corresponding improvement strategies for all aspects of PIHCs. Lastly, how far we are from the lab bench to the consumer market is highlighted, and a comprehensive roadmap starting from cooperative components integration and ending with the future direction of next-generation PIHCs for grid-scale energy storage is clearly described. We anticipate that this review will timely arouse strong interest and attention from both academic and industrial communities to this rising technology and make a revolutionary step forward toward commercial applications.

钾离子混合电容器（PIHC）原则上比传统金属离子混合电容器（MIHC）在低成本、安全性和可靠性方面更具优势，拥有巨大的市场潜力，但在很大程度上仍然是一个未知领域。在此，我们对 PIHC 的最新进展进行了全面回顾，包括基本理解、设备配置和设计原理。然后，讨论了从根本上阻碍PIHC发展的技术障碍，并针对PIHC的各个方面提出了相应的改进策略。最后，强调了我们从实验室到消费市场的距离，并明确描述了从合作组件集成到下一代电网规模储能PIHC的未来方向的全面路线图。我们预计本次综述将及时引起学术界和工业界对这一新兴技术的强烈兴趣和关注，并朝着商业应用迈出革命性的一步。