Effects of Particle Size, Electronic Connectivity, and Incoherent Nanoscale Domains on the Sequence of Lithiation in LiFePO4 Porous Electrodes

• DOI: 10.1002/adma.201502276
• Publication Date: 2015-10-01T06:21:13Z
• Authors: Yiyang Li; Sophie Meyer; Jongwoo Lim; Sang Chul Lee; William E. Gent; Stefano Marchesini; Harinarayan Krishnan; Tolek Tyliszczak; David Shapiro; Arthur L. David K...; William C. Chueh
• Keywords: 540; Physical Chemistry; X-ray chemical imaging; 01 natural sciences; 0104 chemical sciences; Physical sciences; Engineering; LiFePO4; Chemical sciences; Chemical Sciences; Physical Sciences; ptychography; particle size dependence; Nanoscience & Nanotechnology

High-resolution X-ray microscopy is used to investigate the sequence of lithiation in LiFePO4 porous electrodes. For electrodes with homogeneous interparticle electronic connectivity via the carbon black network, the smaller particles lithiate first. For electrodes with heterogeneous connectivity, the better-connected particles preferentially lithiate. Correlative electron and X-ray microscopy also reveal the presence of incoherent nanodomains that lithiate as if they are separate particles.