Urea, a basic chemical compound, holds diverse applications across numerous domains, ranging from agriculture to energy storage. Of particular interest is its role as a hydrogen bond donor (HBD). This specific characteristic has propelled its utilization as an essential component in crafting deep eutectic solvents (DESs) for battery electrolytes. Incorporating urea into DESs presents a promising avenue to address environmental concerns associated with traditional electrolytes, thereby advancing battery technology. Conventional electrolytes, often composed of hazardous and combustible solvents, pose significant environmental risks upon improper disposal potentially contaminating soil and water and threatening both human health and ecosystems. Consequently, there is a pressing need for eco-friendly alternatives capable of upholding high performance and safety standards. DESs, categorized as organic salts resulting from the blending of two or more compounds, have emerged as promising contenders for the next generation of electrolytes. Urea stands out among DES electrolytes by enhancing ion transport, widening the electrochemical window stability (ESW), and prolonging battery cycle life. Further, its non-toxic nature, limited flammability, and elevated thermal stability play pivotal roles in mitigating environmental concerns and safety issues associated with traditional electrolytes. Laboratory testing of urea-based DES electrolytes across various battery systems, including Al-ion, Na-ion, and Zn-ion batteries, has already been demonstrated. This review examines the evolution of urea-based DES electrolytes by elucidating their structure, molecular interaction mechanisms, performance attributes, and preparation methodologies.

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尿素基低共熔溶剂作为电池技术电解质的最新进展：批判性评论

尿素是一种基本化合物，在从农业到能源储存等众多领域具有多种应用。特别令人感兴趣的是它作为氢键供体（HBD）的作用。这一特性推动了其作为电池电解质低共熔溶剂 (DES) 的重要组成部分的应用。将尿素纳入 DES 为解决与传统电解质相关的环境问题提供了一条有前途的途径，从而推动电池技术的发展。传统电解质通常由危险且可燃的溶剂组成，如果处理不当，会造成重大环境风险，可能污染土壤和水，威胁人类健康和生态系统。因此，迫切需要能够维护高性能和安全标准的环保替代品。DES 被归类为由两种或多种化合物混合而成的有机盐，已成为下一代电解质的有希望的竞争者。尿素通过增强离子传输、拓宽电化学窗口稳定性 (ESW) 和延长电池循环寿命，在 DES 电解质中脱颖而出。此外，其无毒性质、有限的可燃性和较高的热稳定性在减轻与传统电解质相关的环境问题和安全问题方面发挥着关键作用。各种电池系统（包括铝离子、钠离子和锌离子电池）中基于尿素的 DES 电解质的实验室测试已经得到证实。本综述通过阐明尿素基 DES 电解质的结构、分子相互作用机制、性能属性和制备方法来研究其演变。