Ultralight and High Thermal Conductive Current Collector Derived from Polyimide for Advanced LIBs

Currently, the thermal runaway of lithium-ion batteries (LIBs) has become one of its most concerned safety hazards. Therefore, battery cells with high safety and energy density have become the important goal for the development of LIBs. In this work, the ultralight and high thermal conductivity of the Cu@graphene-like thermal film (shortened as Cu@GTF) composite current collector with a sandwich structure was derived from polyimide and prepared by the vacuum evaporation method. Compared with the commercial copper foil, the Cu@GTF showed a smaller areal density of <7.0 mg/cm2 (vs 17.50 mg/cm2 of commercial Cu foil) and a higher thermal conductivity of >550 mm2/s (vs 164 mm2/s of Cu foil). Considering its lighter mass, higher thermal conductivity, and reasonable electrical conductivity, the Cu@GTF as a current collector may become a favorable competitor of the commercial Cu foil to meet people's needs for high safety, energy, and performance of LIBs.