在氧电池的放电过程中表面膜的决定因素
Wentao Wang1, Chuan Tan2, Lu He1
1State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, Jiangsu 211816, People's Republic of China.
The journal of physical chemistry letters
|January 10, 2024
概括
氧电池由于被动化层而出现过早故障. 这项研究量化了碳酸和过氧化的比例,揭示了这些层是如何形成和影响电池性能的.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 氧电池具有较高的理论能量密度.
- 过早的细胞死亡是一个主要的挑战,通常是由电极上的绝缘性被动化层引起的.
- 了解这些层是提高电池寿命和性能的关键.
研究的目的:
- 量化比较碳酸盐与过氧化在氧流电池中的放电过程中的比例.
- 为了研究不同潜力和流速对被动化层形成的影响.
- 为了阐明氧电池中电极被动化的机制.
主要方法:
- 使用流动电池设置进行氧电池测试.
- 在放电过程中,不同的电化学潜力和电解质流量.
- 分析了金电极上的放电产品薄膜的组成和厚度.
主要成果:
- 碳酸与过氧化的比率在低潜力和高流速下显著增加.
- 观察到电极被动化,黄金电极上形成3纳米厚的放电产品薄膜.
- 表面反应路径产生了大量的副产品,有助于被动化.
结论:
- 受碳酸盐/氧化物比率影响的被动化层形成是氧电池故障的关键因素.
- 优化放电条件 (电位和流量) 可以减轻副产品的形成,并延长电池的寿命.
- 对于高能氧电池,需要进一步研究控制排放产品成分.
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