High Voltage Mg-Ion Battery Cathode via a Solid Solution Cr–Mn Spinel Oxide

Kwon, Bob Jin; Yin, Liang; Park, Haesun; Parajuli, Prakash; Kumar, Khagesh; Kim, Sanghyeon; Yang, Mengxi; Murphy, Megan; Zapol, Peter; Liao, Chen; Fister, Timothy T.; Klie, Robert F.; Cabana, Jordi; Vaughey, John T.; Lapidus, Saul H.; Key, Baris

doi:10.1021/acs.chemmater.0c01988

DOE OSTI · 1756770

High Voltage Mg-Ion Battery Cathode via a Solid Solution Cr–Mn Spinel Oxide

Kwon, Bob Jin·Yin, Liang·Park, Haesun·Parajuli, Prakash·Kumar, Khagesh·Kim, Sanghyeon·Yang, Mengxi·Murphy, Megan·Zapol, Peter·Liao, Chen·Fister, Timothy T.·Klie, Robert F.·Cabana, Jordi·Vaughey, John T.·Lapidus, Saul H.·Key, Baris

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Abstract

We discuss how lattice Mg 2+ in a tailored solid solution spinel, MgCrMnO 4 , is electrochemically utilized at high Mn-redox potentials in a nonaqueous electrolyte. Complementary evidence from experimental and theoretical analyses supports bulk Mg 2+ (de)intercalation throughout the designed oxide frame where strong electrostatic interaction between Mg 2+ and O 2- exists. Mg/Mn antisite inversion in the spinel is lowered to similar to 10% via postannealing at 350 degrees C to further improve Mg 2+ mobility. Spinel lattice is preserved upon removal of Mg 2+ without any phase transformations, denoting structural stability at the charged state at a high potential similar to 3.0 V (vs Mg/Mel. Clear remagnesiation upon first discharge, harvesting up to similar to 180 Wh/kg at 60 degrees C is shown. In the remagnesiated state, insertion of Mg 2+ into interstitial sites in the spinel is detected, possibly resulting in partial reversibility which needs to be addressed for structural stability. The observations constitute a first clear path to the development of a practical high voltage Mg-ion cathode using a spinel oxide.

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Kwon, Bob Jin, Yin, Liang, Park, Haesun, Parajuli, Prakash, Kumar, Khagesh, Kim, Sanghyeon, Yang, Mengxi, Murphy, Megan, Zapol, Peter, Liao, Chen, Fister, Timothy T., Klie, Robert F., Cabana, Jordi, Vaughey, John T., Lapidus, Saul H., Key, Baris. 2020-07-14. High Voltage Mg-Ion Battery Cathode via a Solid Solution Cr–Mn Spinel Oxide. https://doi.org/10.1021/acs.chemmater.0c01988

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