Details

Autor(en) / Beteiligte

• Li, Zhenyou
• Vinayan, Bhaghavathi P.
• Jankowski, Piotr
• Njel, Christian
• Roy, Ananyo
• Vegge, Tejs
• Maibach, Julia
• Lastra, Juan Maria García
• Fichtner, Maximilian
• Zhao‐Karger, Zhirong

Titel

Multi‐Electron Reactions Enabled by Anion‐Based Redox Chemistry for High‐Energy Multivalent Rechargeable Batteries

Ist Teil von

• Angewandte Chemie (International ed.), 2020-07, Vol.59 (28), p.11483-11490

Auflage

International ed. in English

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The development of multivalent metal (such as Mg and Ca) based battery systems is hindered by lack of suitable cathode chemistry that shows reversible multi‐electron redox reactions. Cationic redox centres in the classical cathodes can only afford stepwise single‐electron transfer, which are not ideal for multivalent‐ion storage. The charge imbalance during multivalent ion insertion might lead to an additional kinetic barrier for ion mobility. Therefore, multivalent battery cathodes only exhibit slope‐like voltage profiles with insertion/extraction redox of less than one electron. Taking VS4 as a model material, reversible two‐electron redox with cationic–anionic contributions is verified in both rechargeable Mg batteries (RMBs) and rechargeable Ca batteries (RCBs). The corresponding cells exhibit high capacities of >300 mAh g−1 at a current density of 100 mA g−1 in both RMBs and RCBs, resulting in a high energy density of >300 Wh kg−1 for RMBs and >500 Wh kg−1 for RCBs. Mechanistic studies reveal a unique redox activity mainly at anionic sulfides moieties and fast Mg2+ ion diffusion kinetics enabled by the soft structure and flexible electron configuration of VS4. Put into storage: Cathodes allowing fast cation mobility are demonstrated in a VS4 structure for high‐energy, multivalent (Mg and Ca) batteries. The flexible VS4 electronic structure enables cationic and anionic redox processes with multi‐electron transfer.