Starch acetate and carboxymethyl starch as green and sustainable polymer electrolytes for high performance lithium ion batteries

Starch-based electrolytes are used here to achieve safe, efficient, inexpensive, and eco-friendly lithium ion batteries (LIBs). Carboxymethyl starch (CMS) and starch acetate (SA) are synthesized as starch amorphous derivatives from corn starch, and then crosslinked by poly(vinyl alcohol) (PVA) to form a polymer network. In the following, the electrochemical properties of the obtained electrolytes in both solid and gel states are investigated. At room temperature, the ionic conductivity for solid CMS and gel SA electrolytes are 9.2*10-3 S cm−1 and 1.13*10-2 S cm−1, respectively. Other remarkable results of these electrolytes are the wide electrochemical stability window, stable cyclic performance, charge capacity higher than 210 mAh/g, CE = 100 % before 10 cycles charge–discharge for both CMS and SA, and good electrode/electrolyte compatibility. The unparalleled electrochemical performance of CMS and SA, along with their unique properties, make them a unique alternative to liquid electrolytes in LIB.