Reversible Electrochemical Interface of Mg Metal and Conventional Electrolyte Enabled by Intermediate Adsorption

Journal Article · Wed Dec 04 00:00:00 EST 2019 · ACS Energy Letters

DOI:https://doi.org/10.1021/acsenergylett.9b02211· OSTI ID:1639082

Wang, Hui  ^[1]; Feng, Xuefei ^[2]; Chen, Ying ^[1]; Liu, Yi-Sheng  ^[2]; Han, Kee Sung  ^[1]; Zhou, Mingxia  ^[3]; Engelhard, Mark H.  ^[4]; Murugesan, Vijayakumar  ^[1]; Assary, Rajeev S.  ^[3]; Liu, Tianbiao Leo ^[5]; Henderson, Wesley ^[5]; Nie, Zimin ^[5]; Gu, Meng ^[4]; Xiao, Jie  ^[5]; Wang, Chongmin  ^[4]; Persson, Kristin ^[6]; Mei, Donghai  ^[5]; Zhang, Ji-Guang  ^[5]; Mueller, Karl T.  ^[7]; Guo, Jinghua  ^[2] ; Zavadil, Kevin  ^[8]; Shao, Yuyan  ^[1]; Liu, Jun  ^[5]

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1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joint Center for Energy Storage Research (JCESR), Lemont, IL (United States)
2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Joint Center for Energy Storage Research (JCESR), Lemont, IL (United States)
3. Argonne National Lab. (ANL), Lemont, IL (United States); Joint Center for Energy Storage Research (JCESR), Lemont, IL (United States)
4. Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
5. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
6. Joint Center for Energy Storage Research (JCESR), Lemont, IL (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
7. Joint Center for Energy Storage Research (JCESR), Lemont, IL (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
8. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Joint Center for Energy Storage Research (JCESR), Lemont, IL (United States)

Conventional electrolytes made by mixing simple Mg salts and aprotic solvents, analogous to those in Li-ion batteries, are incompatible with Mg anodes because Mg metal readily reacts with such electrolytes, producing a passivation layer that blocks Mg transport. Here, we report that, through tuning a conventional electrolyte - Mg(TFSI) (TFSI is N(SO CF ) ) - with an Mg(BH ) cosalt, highly reversible Mg plating/stripping with a high Coulombic efficiency is achieved by neutralizing the first solvation shell of Mg cationic clusters between Mg and TFSI and enhanced reductive stability of free TFSI . A critical adsorption step between Mg atoms and active Mg cation clusters involving BH anions is identified to be the key enabler for reversible Mg plating/stripping through analysis of the distribution of relaxation times (DRT) from operando electrochemical impedance spectroscopy (EIS), operando electrochemical X-ray absorption spectroscopy (XAS), nuclear magnetic resonance (NMR), and density functional theory (DFT) calculations. 2+ 2+ - - 2+ - - 0 - 2 2 3 2 4 2 4

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC04-94AL85000; AC05-76RL01830; AC02-06CH11357; AC02-05CH11231
• OSTI ID: 1639082
• Alternate ID(s): OSTI ID: 1638713; OSTI ID: 1780735
• Report Number(s): SAND-2020-6649J; PNNL-SA-144809; 687020
• Journal Information: ACS Energy Letters, Vol. 5, Issue 1; ISSN 2380-8195
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Interfaces
adsorption
electrodeposition
cluster chemistry
electrolytes