Anion-enrichment interface enables high-voltage anode-free lithium metal batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36841872.
- Also identified by DOI 10.1038/s41467-023-36853-x and PMC identifier 9968319.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Aggressive chemistry involving Li metal anode (LMA) and high-voltage LiNi<sub>0.8</sub>Mn<sub>0.1</sub>Co<sub>0.1</sub>O<sub>2</sub> (NCM811) cathode is deemed as a pragmatic approach to pursue the desperate 400 Wh kg<sup>-1</sup>. Yet, their implementation is plagued by low Coulombic efficiency and inferior cycling stability. Herein, we propose an optimally fluorinated linear carboxylic ester (ethyl 3,3,3-trifluoropropanoate, FEP) paired with weakly solvating fluoroethylene carbonate and dissociated lithium salts (LiBF<sub>4</sub> and LiDFOB) to prepare a weakly solvating and dissociated electrolyte. An anion-enrichment interface prompts more anions' decomposition in the inner Helmholtz plane and higher reduction potential of anions. Consequently, the anion-derived interface chemistry contributes to the compact and columnar-structure Li deposits with a high CE of 98.7% and stable cycling of 4.6 V NCM811 and LiCoO<sub>2</sub> cathode. Accordingly, industrial anode-free pouch cells under harsh testing conditions deliver a high energy of 442.5 Wh kg<sup>-1</sup> with 80% capacity retention after 100 cycles.