Role of disorder in limiting the true multi-electron redox in ε-LiVOPO 4

DOI: 10.1039/C8TA06469E

Authors: Jatinkumar Rana (Binghamton University) , Yong Shi (Binghamton University) , Mateusz J. Zuba (Binghamton University) , Kamila M Wiaderek (Argonne National Laboratory) , Jun Feng (Binghamton University) , Hui Zhou (Binghamton University) , Jia Ding (Binghamton University) , Tianpin Wu (Advanced Photon Source) , Giannantonio Cibin (Diamond Light Source) , Mahalingam Balasubramanian (Advanced Photon Source) , Frederick O. Omenya (Binghamton University) , Natasha Chernova (Binghamton University) , Karena W. Chapman (Argonne National Laboratory) , M. Stanley Whittingham (Binghamton University) , Louis F. J. Piper (Binghamton University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Materials Chemistry A

State: Published (Approved)
Published: September 2018
Diamond Proposal Number(s): 18423

Abstract: Recent advances in materials syntheses have enabled ε-LiVOPO4 to deliver capacities approaching, and in some cases exceeding the theoretical value of 305 mA h g-1 for 2Li intercalation, despite its poor electronic and ionic conductivity. However, not all of the capacity corresponds to the true electrochemical intercalation/deintercalation reactions as evidenced upon systematic tracking of V valence through combined operando and rate-dependent ex-situ X-ray absorption study presented herein. Structural disorder and defects introduced in the material by high-energy ball milling impede kinetics of the high-voltage V5+/V4+ redox more severely than the low-voltage V4+/V3+ redox, promoting significant side reaction contributions in the high-voltage region, irrespective of cycling conditions. The present work emphasizes the need for nanoengineering of active materials without compromising their bulk structural integrity in order to fully utilize high-energy density of multi-electron cathode materials.

Subject Areas: Chemistry, Materials, Energy


Instruments: B18-Core EXAFS

Other Facilities: Advanced Photon Source