Sodium metal batteries are a potentially promising energy storage solution due to the abundance and low cost of sodium and high energy density of metal anodes. However, the growth of microstructural metal during cycling remains a crucial safety and performance issue to be addressed. Herein we investigate this process in sodium metal symmetric cells using operando ²³Na nuclear magnetic resonance spectroscopy. We analyse the NMR signal arising from the microstructural sodium metal to obtain quantitative and qualitative information on its growth and morphology, observing significant differences in the evolution of the microstructures for different electrolytes, including ionic liquids with different sodium salt concentrations, water as an additive, and comparing with a more traditional organic electrolyte. The results correlate well with the previously reported cycling performance of these electrolytes, as well as ex situ SEM images of the electrode surface after cycling.

中文翻译：

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通过原位 23Na NMR 波谱研究离子液体电解质钠金属电池中金属微观结构的生长和形貌


钠金属电池是一种有潜力的储能解决方案，因为它的钠含量丰富、成本低且金属阳极的能量密度高。然而，循环过程中微结构金属的生长仍然是一个需要解决的关键安全和性能问题。在此，我们使用原位 ²³Na 核磁共振波谱研究了钠金属对称电池中的这一过程。我们分析了由微结构钠金属产生的 NMR 信号，以获得有关其生长和形态的定量和定性信息，观察不同电解质（包括具有不同钠盐浓度的离子液体、作为添加剂的水）的微观结构演变的显着差异，并与更传统的有机电解质进行比较。结果与先前报道的这些电解质的循环性能以及循环后电极表面的异位 SEM 图像密切相关。