Influence of the Mechanism of Discharge Product Formation on the Electrochemical Performance and Cyclability of Aprotic Na–O 2 Batteries
Influence of the Mechanism of Discharge Product Formation on the Electrochemical Performance and Cyclability of Aprotic Na–O 2 Batteries
复制标题
放电产物形成机制对非质子Na−O 2 电池电化学性能和循环性能的影响
DOI：
10.1021/acsenergylett.3c01664
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发表时间：
2023
影响因子：
22
通讯作者：
Nikolla, Eranda
中科院分区：
文献类型：
--
作者：
Velinkar, Kunal Kalpesh;Gunten, Alex Von;Greeley, Jeffrey;Nikolla, Eranda
由于比能量密度高，Na-O2电池已成为最先进锂离子电池的潜在替代品。然而，与总体效率和长期稳定性差有关的挑战阻碍了它们的实际应用。了解电极/电解质界面的失活机制对于克服这些挑战至关重要。在此，我们调查的效果的阴极/电解质界面上的放电机制，通过改变甘醇二甲醚-醚电解质溶剂和性质的碳阴极。我们报告说，在碳/电解质界面驱动的表面介导放电的放电电荷能量是敏感的碳阴极的性质。它们的主要失活机制涉及形成不期望的放电产物，这可以通过调整阴极表面来减轻。相反，放电-充电能量学和Na-O2电池的溶液介导的放电过程驱动的失活有有限的依赖于碳阴极。这些发现对有效设计高效稳定的Na-O2电池具有重要意义。
Na–O2batteries have emerged as potential alternatives to state-of-the-art lithium-ion batteries due to their high specific energy density. However, challenges related to poor overall efficiency and long-term stability have hindered their practical application. Understanding the deactivation mechanisms at the electrode/electrolyte interfaces is critical to overcoming these challenges. Herein, we investigate the effect of the cathode/electrolyte interface on the discharge mechanism by varying the glyme-ether electrolyte solvent and the nature of the carbon cathode. We report that discharge–charge energetics at carbon/electrolyte interfaces driven by surface-mediated discharge are sensitive to the nature of the carbon cathode. Their main deactivation mechanism involves the formation of undesired discharged products, which can be mitigated by tuning the cathode surface. Conversely, discharge–charge energetics and deactivation of Na–O2cells driven by a solution-mediated discharge process have limited dependence on the carbon cathode. These findings have implications for effectively designing efficient and stable Na–O2batteries.