Abstract
The conformation of poly(acrylic acid) (PAA) as a function of shear during slurry processing to construct silicon-based anodes is elucidated via rheology-coupled ultra-small-angle neutron scattering (rheo-USANS). Rheo-USANS shows that PAA with encapsulated silicon exists as discrete aggregates that do not interact with one another. As a result, a well-connected matrix of silicon and carbon black dispersed in PAA does not exist; thus, the electrode is inhomogeneous. Raman mapping and X-ray photoelectron spectroscopy were used to confirm the electrode heterogeneity and further understand the cycling properties. These results are correlated to silicon surface chemistry to provide a pathway to making better electrodes.
| Original language | English |
|---|---|
| Pages (from-to) | 13479-13494 |
| Number of pages | 16 |
| Journal | Journal of Physical Chemistry C |
| Volume | 124 |
| Issue number | 24 |
| DOIs | |
| State | Published - Jun 18 2020 |
Funding
Many fruitful discussions/debates and the initial analysis of the data were facilitated by Michael Agamalian (deceased 2019). The authors are greatly indebted to Michael, who declined authorship but continued to work and improve the experiments. The authors thank Steven Trask and Bryant Polzin at the ANL CAMP Facility for supplying the silicon materials. This work (M.K.B-T., B.L.A., A.M.R., G.Y., N.D.P., M.K.K., G.M.V) was supported by the US Department of Energy’s (DOE) Office of Energy Efficiency and Renewable Energy through the Vehicle Technology Office (Brian Cunningham Program Manager). A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by Oak Ridge National Laboratory (M.D. and L.H.). Ultra-small-angle scattering measurements were done by using the USANS instrument at the Spallation Neutron Source. This manuscript has been authored by UT-Battelle LLC under Contract DE-AC05-00OR22725 with DOE. The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ).