Wang Qidi, Wang Jianlin, Heringa Jouke R, Bai Xuedong, Wagemaker Marnix
Department of Radiation Science and Technology, Delft University of Technology, Mekelweg 15, 2629JB Delft, The Netherlands.
State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
ACS Energy Lett. 2024 Jul 11;9(8):3796-3806. doi: 10.1021/acsenergylett.4c01358. eCollection 2024 Aug 9.
One of the primary challenges to improving lithium-ion batteries lies in comprehending and controlling the intricate interphases. However, the complexity of interface reactions and the buried nature make it difficult to establish the relationship between the interphase characteristics and electrolyte chemistry. Herein, we employ diverse characterization techniques to investigate the progression of electrode-electrolyte interphases, bringing forward opportunities to improve the interphase properties by what we refer to as high-entropy solvation disordered electrolytes. Through formulating an electrolyte with a regular 1.0 M concentration that includes multiple commercial lithium salts, the solvation interaction with lithium ions alters fundamentally. The participation of several salts can result in a weaker solvation interaction, giving rise to an anion-rich and disordered solvation sheath despite the low salt concentration. This induces a conformal, inorganic-rich interphase that effectively passivates electrodes, preventing solvent co-intercalation. Remarkably, this electrolyte significantly enhances the performance of graphite-containing anodes paired with high-capacity cathodes, offering a promising avenue for tailoring interphase chemistries.
提高锂离子电池面临的主要挑战之一在于理解和控制复杂的界面相。然而，界面反应的复杂性和其隐蔽性使得难以建立界面相特性与电解质化学之间的关系。在此，我们采用多种表征技术来研究电极-电解质界面相的演变，通过我们所谓的高熵溶剂化无序电解质，为改善界面相性能带来了机会。通过配制一种含有多种商业锂盐、浓度为常规1.0 M的电解质溶液，锂离子的溶剂化相互作用发生了根本性变化。几种盐的共同作用会导致溶剂化相互作用减弱，尽管盐浓度较低，但会形成富含阴离子且无序的溶剂化鞘层。这会诱导形成一种保形、富含无机物的界面相，有效地钝化电极，防止溶剂共嵌入。值得注意的是，这种电解质显著提高了与高容量阴极配对的含石墨阳极的性能，为定制界面相化学提供了一条有前景的途径。
