Insights into the Effects of Electrolyte Composition on the Performance and Stability of FeF2 Conversion‐Type Cathodes
Abstract
As an alternative to commercial Ni‐ and Co‐based intercalation‐type cathode materials, conversion‐type metal fluoride (MFx) cathodes are attracting more interest due to their promises to increase cell‐level energy density when coupled with lithium (Li) or silicon (Si)‐based anodes. Among metal fluorides, iron fluorides (FeF2 and FeF3) are regarded as some of the most promising candidates due to their high capacity, moderately high potential and the very low cost of Fe. In this study, the impacts of electrolyte composition on the performance and stability of nanostructured FeF2 cathodes are systematically investigated. Dramatic impacts of Li salt composition, Li salt concentration, solvent composition, and cycling potential range on the cathode's most critical performance parameters—stability, capacity, rate, and voltage hysteresis are discovered. In contrast to previous beliefs, it is observed that even if the Fe2+ cation dissolution could be avoided, the dissolution of F− anions may still negatively affect cathode performance. Formation of the more favorable cathode solid electrolyte interface (CEI) is found to minimize both processes.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 12, 2019
- Source ID
- 10.1002/aenm.201803323
Entities
People
- Alexandre Magasinski
- D. Gordon
- Gleb Yushin
- Kostiantyn Turcheniuk
- Nasr Bensalah
- Qiao Huang
- Xiaolei Ren
Organizations
- Army Research Office
- Central South University
- Chongqing University
- Georgia Tech
- Qatar National Research Fund
- Qatar University