Effect of crystallite geometries on electrochemical performance of porous intercalation electrodes by multiscale operando investigation

Journal Article · Tue Feb 01 00:00:00 EST 2022 · Nature Materials

DOI:https://doi.org/10.1038/s41563-021-01151-8· OSTI ID:1922197

Luo, Yuting; Bai, Yang; Mistry, Aashutosh; Zhang, Yuwei; Zhao, Dexin; Sarkar, Susmita; Handy, Joseph V.; Rezaei, Shahed; Chuang, Andrew Chihpin; Carrillo, Luis; Wiaderek, Kamila; Pharr, Matt; Xie, Kelvin; Mukherjee, Partha P.; Xu, Bai-Xiang; Banerjee, Sarbajit

Lithium-ion batteries are yet to realize their full promise because of challenges in the design and construction of electrode architectures that allow for their entire interior volumes to be reversibly accessible for ion storage. Electrodes constructed from the same material and with the same specifications, which differ only in terms of dimensions and geometries of the constituent particles, can show surprising differences in polarization, stress accumulation and capacity fade. Here, using operando synchrotron X-ray diffraction and energy dispersive X-ray diffraction (EDXRD), we probe the mechanistic origins of the remarkable particle geometry-dependent modification of lithiation-induced phase transformations in V2O5 as a model phase-transforming cathode. A pronounced modulation of phase coexistence regimes is observed as a function of particle geometry. Specifically, a metastable phase is stabilized for nanometre-sized spherical V2O5 particles, to circumvent the formation of large misfit strains. Spatially resolved EDXRD measurements demonstrate that particle geometries strongly modify the tortuosity of the porous cathode architecture. Greater ion-transport limitations in electrode architectures comprising micrometre-sized platelets result in considerable lithiation heterogeneities across the thickness of the electrode. These insights establish particle geometry-dependent modification of metastable phase regimes and electrode tortuosity as key design principles for realizing the promise of intercalation cathodes. Designing electrode architectures for Li-ion batteries that can be reversibly accessible for ion storage can be challenging. Using operando techniques the mechanistic origin of lithiation-induced phase transformations in a V2O5 model cathode is now clarified.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: National Science Foundation (NSF); Welch Foundation; German Science Foundation
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1922197
• Journal Information: Nature Materials, Vol. 21, Issue 2
• Country of Publication: United States
• Language: English