Publication
Title
Origin of the high capacity manganese-based oxyfluoride electrodes for rechargeable batteries
Author
Abstract
In the quest for high energy density rechargeable batteries, conversion-type cathode materials stand out with their appealing multielectron transfer properties. However, they undergo a series of complex phase transitions upon initial cycling as opposed to conventional intercalation-type materials. Within this category, iron-based mixed-anion solid solutions (FeOxF2-x) have captured the most attention of the battery community, owing to their high theoretical capacity and moderate cyclability. In the meantime, it was recently demonstrated, via a series of electrochemical cycling experiments, the in situ preparation of manganese-based mixed-anion cathode materials based on decomposition of electrolyte salt LiPF6 in the presence of MnO. To take a step forward, we herein report a routine protocol to prepare 220 mAh g(-1)-class composite cathodes. In addition, we provide a comprehensive understanding of the in situ fluorination and locally reversible phase transitions using complementary analytical techniques. The charged phase, with an average Mn oxidation state of ca. +2.8, consists of a highly disordered O-rich cubic-spinel-like core and an F-rich amorphous shell. Upon discharge, lithiation induces further phase transition, forming LiF, MnO, and a lithiated rocksalt-like phase. This work, which we also extended to the iron-based system, offers insights into modification of chemical and electronic properties of electrode materials by in situ fluorination.
Language
English
Source (journal)
Chemistry of materials / American Chemical Society. - Washington, D.C., 1989, currens
Publication
Washington, D.C. : 2018
ISSN
0897-4756 [print]
1520-5002 [online]
Volume/pages
30 :15 (2018) , p. 5362-5372
ISI
000442186500055
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 08.10.2018
Last edited 20.09.2021
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