Effect of the dielectric constant of a liquid electrolyte on lithium metal anodes

Journal Article · 24 January 2019 · Electrochimica Acta

DOI: https://doi.org/10.1016/j.electacta.2019.01.113 · OSTI ID:1497620

Kim, Ju Young ^[1]; Shin, Dong Ok ^[1]; Chang, Taeyong ^[2]; Kim, Kwang Man ^[1]; Jeong, Jiseon ^[3]; Park, Joonam ^[4]; Lee, Yong Min ^[4]; Cho, Kuk Young ^[5]; Phatak, Charudatta ^[6]; Hong, Seungbum ^[2]; Lee, Young-Gi ^[1]

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1. Electronics and Telecommunications Research Institute (ETRI), Daejeon (Republic of Korea)
2. Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Republic of Korea)
3. EnChem Co., Ltd., Cheonan (Republic of Korea)
4. Daegu Gyeongbuk Institute of Science and Technology (DGIST) (Republic of Korea)
5. Hanyang Univ., Ansan (Republic of Korea)
6. Argonne National Lab. (ANL), Lemont, IL (United States)

Lithium metal is considered one of the most promising anode materials for realizing high volumetric and gravimetric energy density, owing to the high specific capacity (~3860 mAh g^-1) and the low electrochemical potential of lithium (-3.04 V vs. the standard hydrogen electrode). However, undesirable dendritic lithium growth and corresponding instability of the solid electrolyte interphase prevent safe and long-term use of lithium metal anodes. Here, this paper presents a simple electrolyte approach to enhance the performance of lithium metal batteries by tuning the dielectric constant of the liquid electrolyte. Electrolyte formulations are designed by changing the concentration of ethylene carbonate to have various dielectric constants. This study confirms that high ethylene carbonate content in a liquid electrolyte enhances the cycling performance of lithium metal batteries because the electric field intensity applied to the electrolyte is reduced in relation to the polarization of the electrolyte and thus allows smooth lithium plating and formation of a stable solid electrolyte interphase. Lastly, we believe that this approach provides an important concept for electrolyte system design suitable to lithium metal batteries.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE; National Research Foundation (NRF) of Korea
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1497620
• Journal Information: Electrochimica Acta, Journal Name: Electrochimica Acta Journal Issue: C Vol. 300; ISSN 0013-4686
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English