Hybrid energy storage devices including support filaments

摘要

A novel hybrid lithium-ion anode material based on coaxially coated Si shells on vertically aligned carbon nanofiber (CNF) arrays. The unique cup-stacking graphitic microstructure makes the bare vertically aligned CNF array an effective Li+ intercalation medium. Highly reversible Li+ intercalation and extraction were observed at high power rates. More importantly, the highly conductive and mechanically stable CNF core optionally supports a coaxially coated amorphous Si shell which has much higher theoretical specific capacity by forming fully lithiated alloy. Addition of surface effect dominant sites in close proximity to the intercalation medium results in a hybrid device that includes advantages of both batteries and capacitors.

主权项

1. An energy storage system comprising:
an electrolyte including one or more charge carriers; a conductive substrate; a plurality of support filaments on the substrate; intercalation material disposed on the support filaments and configured to reversibly adsorb members of the charge carriers within a bulk of the intercalation material, wherein the intercalation layer covers less than 25% of the support filaments; surface effect dominant sites configured to adsorb members of the charge carriers via faradaic interactions, wherein the intercalation material is configured to receive an oxide of the charge carriers from the surface effect dominant sites; and an overlayer on the intercalation material, the overlayer including SiO2.