Effects of Adding Cerium to Lithium on Properties of Lithium Anode

摘要:

研究了在30 ℃的LiOH 碱性水溶液中，添加合金元素Ce对锂负极性能的影响。开路电位下的自腐蚀析氢速率及电化学测试结果表明，添加Ce对锂负极的析氢速率有明显的抑制作用。Ce 添加量为0.08%（质量分数）时，对锂负极的缓蚀效率接近83.3%。SEM观察表明，与纯锂负极相比，Li-Ce 合金负极放电后的表面膜更加致密少孔。XRD分析表明，该表面膜里除了含有LiOH及LiOH·H2O外，还有Ce(OH)3存在，说明在碱性LiOH水溶液电解质中，Li-Ce合金负极表面形成的Ce(OH)3沉淀物在抑制自腐蚀析氢及影响放电电位方面起着关键作用。

Abstract:

The effects of adding cerium to lithium on the properties of lithium anode were studied in alkaline aqueous LiOH electrolyte at 30 °C. Self-corrosion hydrogen evolution rate at open circuit potential and electrochemical experiments show that the magnitude of hydrogen evolution rate is reduced obviously by adding cerium to lithium. As the content of Ce increases to 0.08 wt%, the inhibition efficiency reaches approximately 83.3%. SEM results show that the surface of Li-Ce alloy forms more compact and less porous film than that of pure lithium after discharge. XRD examination proves the presence of Ce(OH)3 in the lithium-cerium alloy film besides LiOH and LiOH·H2O. It is suggested that Ce(OH)3 plays a key role in inhibiting the hydrogen evolution and affecting discharge potential on the surface of lithium-cerium alloy anode in aqueous alkaline LiOH electrolyte.