Aerosol Jet-Printed LFP Cathodes with Bimodal Pore Distribution Improve the Rate Capability of LIB Cells
Rodrigo Rodríguez, L. Jay Deiner, Bang Hung Tsao, Joseph P. Fellner
Abstract
The electrochemical performance of an aerosol jet (AJ)-printed lithium iron phosphate cathode versus an equivalent tape-cast (TC) cathode was evaluated. Rate capability and long-term cell testing demonstrated that at similar mass loadings and thicknesses, the AJ-printed cathodes achieved higher discharge capacities than the TC cathodes. Electron microscopy and X-ray tomography showed a bimodal pore network for the AJ-printed cathode; larger Li-ion-conducting channels were visible at the electrode surface, while a denser cathode structure (akin to a TC cathode) was present near the current collector. Electrochemical impedance calculations revealed that this bimodal pore distribution endowed AJ-printed cathodes with approximately 30% more electrochemically active surface area than their TC cathode counterparts.