(345f) Fibrous Conduction Networks Under Various Calendaring Regimes in Electrospun LiFePO4/C Fibers | AIChE

(345f) Fibrous Conduction Networks Under Various Calendaring Regimes in Electrospun LiFePO4/C Fibers

Authors 

Boyle, K. - Presenter, University of South Florida
Bhethanabotla, V. R., University of South Florida
Thomas, S., University of South Florida
Advanced materials developments, in particular nano-structured materials, show large potential for battery improvements;but face challenges retaining those improvements when inserted into commercial production processes. In addition, battery material advances are often evaluated at low active mass loading per unit area leading to performance demonstrations at modest practical energy densities.

Calendaring is a typical process to compact battery electrodes to reduce thickness and increase electrode energy density. Calendaring reduces inter-particle distance within a cathode, improving short range electronic conduction and increases active material density; however, this improvement must be balanced against both reductions in void space (i.e. electrolyte penetration) and potential reductions in long range electronic conduction networks.

We use a fibrous carbon matrix as a conductive enhancement to Lithium Iron Phosphate/Carbon (LFP/C) cathode material, produced via electrospinning. This fibrous carbon offers a route to longer range conductive networks that maintain conductive paths under higher calendaring regimes. The electrospun composite LFP/C fibers are made up of thinly coated LFP crystalites within a fibrous carbon matrix. These electrospun fibers provide control over fiber diameter, crystallite size, and cystalite coating thickness for morphology/composition variation through a scalable process.

We report the resilience of conductive networks in electrospun fibrous LFP cathode material to various calendaring regimes, including the range of active mass loadings and void fractions. We review potential for increased practical energy density from electrospun fibrous LFP cathode materials.