دورية أكاديمية

Potassium Fluoride and Carbonate Lead to Cell Failure in Potassium-Ion Batteries

التفاصيل البيبلوغرافية
العنوان: Potassium Fluoride and Carbonate Lead to Cell Failure in Potassium-Ion Batteries
المؤلفون: Andrew W. Ells (11649423), Richard May (2606566), Lauren E. Marbella (1481389)
سنة النشر: 2021
المجموعة: Smithsonian Institution: Digital Repository
مصطلحات موضوعية: Biophysics, Biochemistry, Microbiology, Cell Biology, Physiology, Immunology, Hematology, Space Science, Chemical Sciences not elsewhere classified, potentially cheaper technologies, known additive used, increased interfacial resistance, g ., na, form insoluble kf, entirely new approaches, abundant alkali metals, sacrificial decomposition aid, results strongly suggest, 6 , 3 , 2 , ray photoelectron spectroscopy, electrochemical impedance spectroscopy, electrolyte decomposition pathways, poor k transport, favorable sei components, 19 , kib electrolyte engineering, electrolyte engineering
الوصف: While Li-ion is the prevailing commercial battery chemistry, the development of batteries that use earth-abundant alkali metals (e.g., Na and K) alleviates reliance on Li with potentially cheaper technologies. Electrolyte engineering has been a major thrust of Li-ion battery (LIB) research, and it is unclear if the same electrolyte design principles apply to K-ion batteries (KIBs). Fluoroethylene carbonate (FEC) is a well-known additive used in Li-ion electrolytes because the products of its sacrificial decomposition aid in forming a stable solid electrolyte interphase (SEI) on the anode surface. Here, we show that FEC addition to KIBs containing hard carbon anodes results in a dramatic decrease in capacity and cell failure in only two cycles, whereas capacity retention remains high (> 90% over 100 cycles at C/10 for both KPF 6 and KFSI) for electrolytes that do not contain FEC. Using a combination of 19 F solid-state nuclear magnetic resonance (SSNMR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS), we show that FEC decomposes during galvanostatic cycling to form insoluble KF and K 2 CO 3 on the anode surface, which correlates with increased interfacial resistance in the cell. Our results strongly suggest that KIB performance is sensitive to the accumulation of an inorganic SEI, likely due to poor K transport in these compounds. This mechanism of FEC decomposition was confirmed in two separate electrolyte formulations using KPF 6 or KFSI. Interestingly, the salt anions do not decompose themselves, unlike their Li analogues. Insight from these results indicates that electrolyte decomposition pathways and favorable SEI components are significantly different in KIBs and LIBs, suggesting that entirely new approaches to KIB electrolyte engineering are needed.
نوع الوثيقة: article in journal/newspaper
اللغة: unknown
العلاقة: https://figshare.com/articles/journal_contribution/Potassium_Fluoride_and_Carbonate_Lead_to_Cell_Failure_in_Potassium-Ion_Batteries/16934223Test
DOI: 10.1021/acsami.1c15174.s001
الإتاحة: https://doi.org/10.1021/acsami.1c15174.s001Test
حقوق: CC BY-NC 4.0
رقم الانضمام: edsbas.88B6EC65
قاعدة البيانات: BASE