Abstract
AbstractThe key to increasing the energy density of lithium‐ion batteries is to incorporate high contents of extractable Li into the cathode. Unfortunately, this triggers formidable challenges including structural instability and irreversible chemistry under operation. Here, we report a new kind of ultra‐high Li compound: Li4+xMoO5Fx (1≤x≤3) for cathode with an unprecedented level of electrochemically active Li (>3 Li+ per formula), delivering a reversible capacity up to 438 mAh g−1. Unlike other reported Li‐rich cathodes, Li4+xMoO5Fx presents distinguished structure stability to immunize against irreversible behaviors. Through spectroscopic and electrochemical techniques, we find an anionic redox‐dominated charge compensation with negligible oxygen release and voltage decay. Our theoretical analysis reveals a “reductive effect” of high‐level fluorination stabilizes the anionic redox by reducing the oxygen ions in pure‐Li conditions, enabling a facile, reversible, and high Li‐portion cycling.
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 call
