Question

Why etheyelene carbonate is used as electrolye for lithium ion batteries?

Answer 1

Ethylene carbonate (EC) provides a Li+ ion-conducting but electronically- passivating layer on the negative electrodes such as carbon. Since, EC is solid at room temperature, it is mixed with propylene carbonate (PC) to yield a liquid electrolyte. PC alone does not form a good passivating layer on negative Li-based electrodes.