(Invited) Colossal Intercalation Capacity: Sci-Fi Idea or Intrinsic Property?

Invited Lecture: ECS Meeting Abstract, MA2021-02, A02: Sodium and Lithium Intercalation Chemistry for Rechargeable Batteries – Special Symposium in Honor of Claude Delmas

Presenter: Radostina Stoyanova, Co-authors: Mariya Kalapsazova and Ekaterina Zhecheva

The full presentation is available here:

https://iopscience.iop.org/article/10.1149/MA2021-022202mtgabs

Abstract: Achieving colossal capacity at intercalation electrodes is a research dream accompanying the development of batteries from their beginning. Herein, we demonstrate that the colossal intercalation capacity could be achieved when the cations and anions of the intercalation electrode participate in a synchronic way in the redox electrochemical reaction. The proof-of-concept is built on the surface and structural engineering of three layered sodium nickel-manganese oxide, P3-Na_xNi_1/2Mn_1/2O₂, exhibiting a unique capability to intercalate both Li⁺ and Na⁺. The dual ‘cation-oxygen’ redox reactions during Li⁺/Na⁺ intercalation is unlocked by selective substitution of nickel ions in P3-Na_xNi_1/2Mn_1/2O₂ with intercalation inactive ions such as Mg²⁺ and Ti⁴⁺. The modification of P3-Na_xNi_1/2Mn_1/2O₂ with oxygen-storage material contributes to the stabilization the oxygen redox reaction by avoiding the side surface reactivity. Finally, an outlook of further steps for activation of dual ‘cation-oxygen’ redox reactions is suggested.