Abstract
AbstractThe performance of Li‐ion batteries (LIBs) is highly dependent on their interfacial chemistry, which is regulated by electrolytes. Conventional electrolyte typically contains polar solvents to dissociate Li salts. Herein we report a weakly solvating electrolyte (WSE) that consists of a pure non‐polar solvent, which leads to a peculiar solvation structure where ion pairs and aggregates prevail under a low salt concentration of 1.0 M. Importantly, WSE forms unique anion‐derived interphases on graphite electrodes that exhibit fast‐charging and long‐term cycling characteristics. First‐principles calculations unravel a general principle that the competitive coordination between anions and solvents to Li ions is the origin of different interfacial chemistries. By bridging the gap between solution thermodynamics and interfacial chemistry in batteries, this work opens a brand‐new way towards precise electrolyte engineering for energy storage devices with desired properties.
Highlights
IntroductionThe Nobel Prize in Chemistry 2019 rewarded the development of Li-ion batteries (LIBs) as this light-weight, rechargeable, and ubiquitous energy storage device has profoundly revolutionized our modern life during the past 30 years.[1,2,3] The increasing demands of electric vehicles and grid energy storage is gradually pushing the performance of LIBs to their limits, including high energy density, fast charging, high safety, long life and low cost.[4,5,6,7,8] To meet these high bars, current LIBs must venture into more challenging territories such as Li/Si anodes,[9,10,11] high-voltage/capacity cathodes,[12,13,14] and aqueous LIBs.[15,16,17] Eventually, the challenges for these aggressive battery chemistries are partially or completely passed on to designing advanced electrolytes.[18] The electrolytes in LIBs serve as an ionic conductor, and largely determine the electrode/electrolyte interfacial chemistry.[19] Because the performance of LIBs is strongly dependent on the electrode/electrolyte interface, developing state-of-the-art electrolytes is essential to live up to the high technological expectations
We report a novel weakly-solvating electrolyte (WSE) that consists of a pure non-polar solvent, which leads to a peculiar solvation structure where ion pairs and aggregates prevail under a low salt concentration of 1.0 M
The Li+– coordinated ethylene carbonate (EC) is reduced on graphite electrode to form a desirable solid electrolyte interphase (SEI), which is contributed by the typical solvent-derived interfacial chemistry
Summary
The Nobel Prize in Chemistry 2019 rewarded the development of Li-ion batteries (LIBs) as this light-weight, rechargeable, and ubiquitous energy storage device has profoundly revolutionized our modern life during the past 30 years.[1,2,3] The increasing demands of electric vehicles and grid energy storage is gradually pushing the performance of LIBs to their limits, including high energy density, fast charging, high safety, long life and low cost.[4,5,6,7,8] To meet these high bars, current LIBs must venture into more challenging territories such as Li/Si anodes,[9,10,11] high-voltage/capacity cathodes,[12,13,14] and aqueous LIBs.[15,16,17] Eventually, the challenges for these aggressive battery chemistries are partially or completely passed on to designing advanced electrolytes.[18] The electrolytes in LIBs serve as an ionic conductor, and largely determine the electrode/electrolyte interfacial chemistry.[19] Because the performance of LIBs is strongly dependent on the electrode/electrolyte interface, developing state-of-the-art electrolytes is essential to live up to the high technological expectations It is well-established that the interfacial chemistry on electrodes is closely correlated to the solvation structure of electrolytes. First-principles calculations unravel a fundamental rationale that the relative binding energy between anions/solvents and Li+ dictates the electrode/electrolyte interfacial chemistry, which blazes a new trail in precise electrolyte design for future batteries
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
