Aqueous potassium‐ion batteries (AKIBs) with mild aqueous electrolytes can significantly mitigate the safety and environmental issues raised from traditional nonaqueous batteries, positioning them as promising candidates for grid‐scale applications. Nonetheless, the progression of AKIBs is currently impeded by the insufficient energy density, largely attributed to the limited voltage window of aqueous electrolytes. This review aims to introduce foundational knowledge about aqueous batteries, illustrates recent advancements in AKIBs, and offers valuable perspectives on designing electrode materials and optimizing electrolytes. To provide a systematic overview, the focus is on the following seven key sections: i) development history, ii) electrode materials, iii) electrolyte design, iv) current collectors, v) aqueous interphase chemistry, vi) full cell configurations, and vii) future prospects. Finally, constructive insights and suggestions are provided for the development of AKIBs with higher energy density.

中文翻译：

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全面了解水性钾离子电池


具有温和水性电解质的水性钾离子电池 （AKIB） 可以显著缓解传统非水电池带来的安全和环境问题，使其成为电网规模应用的有前途的候选者。尽管如此，AKIBs 的发展目前受到能量密度不足的阻碍，这主要归因于水性电解质的电压窗口有限。本综述旨在介绍有关水系电池的基础知识，说明 AKIBs 的最新进展，并为设计电极材料和优化电解质提供有价值的观点。为了提供系统的概述，重点放在以下七个关键部分：i） 发展历史，ii） 电极材料，iii） 电解质设计，iv） 集流体，v） 水性相间化学，vi） 全电池配置，以及 vii） 未来前景。最后，为开发具有更高能量密度的 AKIBs 提供了建设性的见解和建议。