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Cu Foil, a thin sheet of Cu, is the common anode current collector in commercial lithium ion batteries (LIBs) which accounts for ∼ 10 wt% of the total cell weight. However, thickness reduction of LIB-based Cu foils below 6 μm has been limited by the incapability of conventional rolling annealing or electrodeposition process. We here report a new type of Cu foil, so called Cu nanowire foil (CuNW foil), for use as an LIB anode current collector. We fabricate Cu NW foils by rolling press Cu nanowire fabric to reduce the thickness down to ∼1.5 μm with an areal weight down to ∼1.2 mg cm−2 and a density approximately 96% to that of bulk Cu. The rough surface and porous structure of CuNW foil enable better wetting and adhering properties of graphite slurry on foil. In full cell examination, a cell of a areal capacity of 3 mAh cm−2 exhibits 83.6% capacity retention for 600 cycles at 0.6 C that meets the standard specification of most commercial LIBs. As a proof-of-concept of demonstration, we fabricate a 700 mA pouch-type battery implemented with graphite-Cu NWs foil anodes to serve as energy supply to operate electronic devices.

Metallic nanostructures possessing higher surface-to-volume ratio provide a more accessible surface to catalyze chemical reactions compared to the bulk materials. However, scaling up the nanostructures remains complicated and limits the applications as industrial catalysis. Here, we demonstrate a facile method to fabricate a robust and versatile Cu nanostructure at a centimeter scale as an efficient photothermal catalytic reactor. By drop-casting the solution of Cu nanowires into a Teflon mold after solvent evaporation followed by annealing in the H2/Ar atmosphere, a Cu nanowire fabric possessing a network structure with a high density of porosity is formed. The Cu fabric exhibits a strong absorptance at the spectral range of 400–1200 nm owing to the interband transition, the surface plasmon resonances of Cu nanowires with their near-field coupling, and “light trapped effect” in the network structures. Exposure to 808 nm laser allows for the elevation of the temperature across the whole structure within 2 s and maintaining a stable temperature up to 250 °C for 2 h. A heterogeneous copper-catalyzed azide-alkyne cycloaddition reaction is performed using Cu nanowire fabric illuminated by an 808 nm laser. A repeatable yield of >90% with a reaction time of 4 h, an order of magnitude shorter than conventional copper catalysts at ambient temperature, is achieved suggesting the Cu nanowire fabric as a robust photothermal catalytic reactor.