Inorganic Compounds as Binders for Si-Alloy Anodes

Abstract

The inorganic compounds, lithium polysilicate (Li 2 Si 5 O 11 ), sodium polyphosphate ((NaPO 3 ) n ), and lithium phosphate monobasic (H 2 LiPO 4 ) were investigated as the sole binders in Si-alloy and graphite electrodes for Li cells. Surprisingly, the coating quality and cycling performance of Si-alloy anodes with these inorganic binders is similar to those electrodes using the state of the art lithium polyacrylate (LiPAA) organic binder. Graphite electrodes with inorganic binders show good cycling despite having poor coating quality. Graphite electrodes with lithium polysilicate binder have three times the binder volume than expected, indicating that this binder has an open framework microstructure.