title: High Areal Capacity Si/LiCoO2Batteries from Electrospun Composite Fiber Mats.
abstract: Freestanding nanofiber mat Li-ion battery anodes containing Si nanoparticles, carbon black, and poly(acrylic acid) (Si/C/PAA) are prepared using electrospinning. The mats are compacted to a high fiber volume fraction (≈0.85), and interfiber contacts are welded by exposing the mat to methanol vapor. A compacted+welded fiber mat anode containing 40 wt % Si exhibits high capacities of 1484 mA h g-1(3500 mA h g-1Si ) at 0.1 C and 489 mA h g-1at 1 C and good cycling stability (e.g., 73 % capacity retention over 50 cycles). Post-mortem analysis of the fiber mats shows that the overall electrode structure is preserved during cycling. Whereas many nanostructured Si anodes are hindered by their low active material loadings and densities, thick, densely packed Si/C/PAA fiber mat anodes reported here have high areal and volumetric capacities (e.g., 4.5 mA h cm-2and 750 mA h cm-3, respectively). A full cell containing an electrospun Si/C/PAA anode and electrospun LiCoO2-based cathode has a high specific energy density of 270 Wh kg-1. The excellent performance of the electrospun Si/C/PAA fiber mat anodes is attributed to the: i) PAA binder, which interacts with the SiOxsurface of Si nanoparticles and ii) high material loading, high fiber volume fraction, and welded interfiber contacts of the electrospun mats.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Ethan C
authors.initials: EC
authors.lastname: Self
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Naguib
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
authors.forename: Rose E
authors.initials: RE
authors.lastname: Ruther
authors.affiliation: Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Emily C
authors.initials: EC
authors.lastname: McRen
authors.affiliation: Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Ryszard
authors.initials: R
authors.lastname: Wycisk
authors.affiliation: Energy Storage and Distributed Resources Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
authors.forename: Gao
authors.initials: G
authors.lastname: Liu
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
authors.forename: Jagjit
authors.initials: J
authors.lastname: Nanda
authors.affiliation: Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37235, USA.
authors.forename: Peter N
authors.identifier: 0000-0001-5115-7276
authors.initials: PN
authors.lastname: Pintauro
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D010087:Oxides; C491691:lithium cobalt oxide; D003035:Cobalt; D012825:Silicon
keywords: areal capacity; li-ion battery; nanostructures; silicon; volumetric capacity