Energy storage devices, battery cells, and batteries of the present technology include a current collector including a polymer film coupled with a plurality of wires of a metal-containing material. The current collector may include a first region and a second region. The first region may be characterized by an extension of the metal-containing material. The polymer film may be contained within the second region of the current collector. Additionally, the plurality of wires may extend from the extension of the metal-containing material along the polymer film.