Journal of Power Sources ( IF 8.1 ) Pub Date : 2018-02-17 , DOI: 10.1016/j.jpowsour.2018.01.049 Moran Balaish , Yair Ein-Eli
Adding immiscible perfluorocarbons (PFCs), possessing superior oxygen solubility and diffusivity, to a free-standing (metal-free and binder-free) CNTs air-electrode tissues with a meso-pore structure, fully maximized the advantages of PFCs as oxygenated-species' channels-providers. The discharge behavior of hybrid PFCs-CNT Li-O2 systems demonstrated a drastic increase in cell capacity at high current density (0.2 mA cm−2), where oxygen transport limitations are best illustrated. The results of this research revealed several key factors affecting PFCs-Li-O2 systems. The incorporation of PFCs with higher superoxide solubility and oxygen diffusivity, but more importantly higher PFCs/electrolyte miscibility, in a meso-pore air-electrode enabled better exploitation of PFCs potential. Consequently, the utilization of the air-electrode' surface area was enhanced via the formation of artificial three phase reaction zones with additional oxygen transportation routes, leading to uniform and intimate Li2O2 deposit at areas further away from the oxygen reservoir. Associated mechanisms are discussed along with insights into an improved Li-O2 battery system.
中文翻译:
用于Li-O 2电池的介孔碳纳米管(CNTs)组织-全氟化碳(PFCs)混合空气电极
向具有中孔结构的独立式(无金属和无粘结剂)CNT空气电极组织中添加具有优异的氧溶解性和扩散性的不混溶的全氟化碳(PFC),从而充分发挥了PFC作为含氧物种的优势。渠道提供商。杂化PFCs-CNT Li-O 2系统的放电行为证明了在高电流密度(0.2 mA cm -2)下电池容量的急剧增加,其中最能说明氧气的传输限制。这项研究的结果揭示了影响PFCs-Li-O 2的几个关键因素系统。在中孔空气电极中掺入具有更高的超氧化物溶解度和氧扩散性,但更重要的是具有更高的PFC /电解质混溶性的PFC,可以更好地利用PFC的潜力。因此,通过形成具有附加氧气传输路径的人工三相反应区,可以提高空气电极表面积的利用率,从而在距氧气池更远的区域产生均匀且紧密的Li 2 O 2沉积物。讨论了相关的机制以及对改进的Li-O 2电池系统的见解。