Yuan Zijie, Wang Yongjing, Chen Yaqi, Zhu Xiaodong, Xiong Shizhao, Song Zhongxiao
State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China.
Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, China.
ChemSusChem. 2024 Sep 23;17(18):e202400164. doi: 10.1002/cssc.202400164. Epub 2024 May 21.
Cycling aging is the one of the main reasons affecting the lifetime of lithium-ion batteries and the contribution of aluminum current collector corrosion to the ageing is not fully recognized. In general, aluminum is corrosion resistant to electrolyte since a non-permeable surface film of alumina is naturally formed. However, corrosion of aluminum current collector can still occur under certain conditions such as lithium bis(fluorosulfonyl)imide (LiFSI)-based electrolyte or high voltage. Herein, we investigates the corrosion of aluminum current collector in the electrolyte of 1.2 M LiFSI in ethylene carbonate (EC) and ethyl methyl carbonate (EMC) mixed solvents. The electrochemical results shows that the corrosion current of aluminum is enhanced by cycling time and potential, which is correlated with the surface species and morphology. The formation of AlF, which is induced by deep penetration of F anions through surface passivation film, leads to internal volume change and the surface crack in the end. Our work will be inspiring for future development of high-energy-density and high-power-density lithium-ion batteries in which the LiFSI salt will be intensively used.
循环老化是影响锂离子电池寿命的主要原因之一，而铝集流体腐蚀对老化的贡献尚未得到充分认识。一般来说，铝对电解质具有耐腐蚀性，因为会自然形成一层不可渗透的氧化铝表面膜。然而，在某些条件下，如基于双（氟磺酰）亚胺锂（LiFSI）的电解质或高电压下，铝集流体仍会发生腐蚀。在此，我们研究了铝集流体在碳酸亚乙酯（EC）和碳酸甲乙酯（EMC）混合溶剂中1.2 M LiFSI电解质中的腐蚀情况。电化学结果表明，铝的腐蚀电流随循环时间和电位的增加而增大，这与表面物种和形态有关。F阴离子通过表面钝化膜的深度渗透诱导AlF的形成，最终导致内部体积变化和表面裂纹。我们的工作将为未来大量使用LiFSI盐的高能量密度和高功率密度锂离子电池的发展提供启示。
