Zarrabeitia Maider, Gomes Chagas Luciana, Kuenzel Matthias, Gonzalo Elena, Rojo Teófilo, Passerini Stefano, Muñoz-Márquez Miguel Ángel
CIC Energigune , Parque Tecnológico de Álava , Albert Einstein 48 , 01510 Miñano , Spain.
Helmholtz Institute Ulm (HIU) , Helmholtzstrasse 11 , 89081 Ulm , Germany.
ACS Appl Mater Interfaces. 2019 Aug 14;11(32):28885-28893. doi: 10.1021/acsami.9b07963. Epub 2019 Aug 2.
The electrochemical properties of P2-NaMnFeTiO layered oxide, which is a promising cathode material for rechargeable Na-ion batteries (NIBs), are evaluated with an optimized in-house ionic liquid (IL)-based electrolyte, and its performance is compared with that using carbonate-based electrolyte. The IL-based system reveals better electrochemical performance at room temperature than the carbonate electrolyte-based one at 0.1C and 1C, especially in terms of cycling stability, with a 97% capacity retention after 100 deep cycles (0.1C). The electrode/electrolyte interface is thoroughly studied in both systems by means of X-ray photoelectron spectroscopy and scanning electron microscopy so as proof that the formed interface is crucial to optimizing the electrochemical performance of NIBs. The carbonate-based system shows a thin, inhomogeneous, and unstable interface layer, while the IL-based one exhibits an even thinner but homogeneous and more stable interface, which may result in safer and longer-lasting NIBs.
P2-NaMnFeTiO层状氧化物是一种很有前景的可充电钠离子电池（NIBs）正极材料，采用优化的基于离子液体（IL）的内部电解质对其电化学性能进行了评估，并将其性能与使用碳酸盐基电解质的情况进行了比较。基于IL的体系在室温下于0.1C和1C时显示出比基于碳酸盐电解质的体系更好的电化学性能，特别是在循环稳定性方面，在100次深度循环（0.1C）后容量保持率为97%。通过X射线光电子能谱和扫描电子显微镜对两个体系中的电极/电解质界面进行了深入研究，以证明形成界面对于优化NIBs的电化学性能至关重要。基于碳酸盐的体系显示出薄的、不均匀的和不稳定的界面层，而基于IL的体系则表现出更薄但均匀且更稳定的界面，这可能会使NIBs更安全、更持久。
