Protein-modified SEI formation and evolution in Li metal batteries  

作　　者：Chenxu Wang Ryan Odstrcil Jin Liu Wei-Hong Zhong 

机构地区：[1]School of Mechanical and Materials Engineering,Washington State University,Pullman,WA 99164,USA

出　　处：《Journal of Energy Chemistry》2022年第10期248-258,I0006,共12页能源化学（英文版）

基　　金：supported by NSF CBET 1929236. Computational resources were provided in part by the Extreme Science and Engineering Discovery Environment (XSEDE) under grant No. MCB170012。

摘　　要：Despite numerous reported lithium metal batteries(LMBs) with excellent cycling performance achieved in labs, transferring the high performing LMBs from lab-scale to industrial-production remains challenging. Therefore, via imitating the stand-still process in battery production, a conventional but important procedure, to investigate the formation and evolution of a solid electrolyte interface(SEI) is particularly important for LMBs. Our previous studies indicate that zein(corn protein)-modified carbonate-ester electrolyte(the most commercialized) effectively improves the performance of LMBs through guiding Li-ions and repairing cracked SEI. Herein, we investigate the formation and evolution of the protein-modified SEIs on Li anodes by imitating the stand-still temperature and duration. A simulation study on the protein denaturation in the electrolyte under different temperatures demonstrates a highly unfolded configuration at elevated temperatures. The experiments show that this heat-treated-zein(H-zein) modified SEI forms quickly and becomes stable after a stand-still process of less than 100 min. Moreover, the Hzein SEI exhibits excellent wetting behavior with the electrolyte due to the highly unfolded protein structures with more functional groups exposed. The Li|Li cell with the H-zein SEI achieves prolonged cycling performance(>360 h vs. ~260 h of the cell with the untreated-zein(U-zein) modified SEI). The Li Fe PO_(4)|Li cell with the H-zein SEI shows much stable long-term cycling performance of capacity retention(70% vs.42% of the cell with U-zein SEI) after 200 cycles. This study confirms that the appropriately treated protein is able to effectively improve the performance of LMBs, and will inspire future studies for the production process of LMBs toward their commercialization.

关 键 词：Protein ZEIN Lithium metal Stand-still BATTERY SEI 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ131.11[化学工程—无机化工]