Open AccessProbing Clustering Dynamics between Silicon and PAA or LiPAA Slurries under Processing Conditions
Author(s) -
Mary K. Burdette-Trofimov,
Beth L. Armstrong,
R.A. Murphy,
Luke Heroux,
M. Doucet,
Alexander M. Rogers,
Gabriel M. Veith
Publication year - 2021
Publication title -
acs applied polymer materials
Language(s) - English
Resource type - Journals
ISSN - 2637-6105
DOI - 10.1021/acsapm.1c00052
Subject(s) - slurry , materials science , polymer , homogeneity (statistics) , silicon , rheology , chemical engineering , composite material , metallurgy , mathematics , engineering , statistics
This work explores the complex interplay between slurry aggregation, agglomeration, and conformation (i.e. shape) of poly(acrylic acid) (PAA) and lithiated poly(acrylic acid) (LiPAA) based silicon slurries as a function of shear rate, and the resulting slurry homogeneity. These values were measured by small angle neutron scattering (SANS) and rheology coupled ultra-small angle neutron scattering (rheo-USANS) at conditions relevant to battery electrode casting. Different binder solution preparation methods, either a ball mill (BM) process or a planetary centrifugal mixing (PCM) process, dramatically modify the resulting polymer dynamics and organization around a silicon material. This is due to the different energy profiles of mixing where the more violent and higher energy PCM causes extensive breakdown and reformation of the binder, which is now likely in a branched conformation, while the lower energy BM results in simply lower molecular weight linear polymers. The break down and reorganization of the polymer structure affects silicon slurry homogeneity, which affects subsequent electrode architecture.