In some embodiments, (see FIG. 7B) a metal layer 720 (e.g., copper, nickel, or other suitable metal that does not readily alloy with lithium during charging or discharging of the battery) is deposited (e.g., by sputtering copper with no oxygen) on one or more major faces (e.g., the top and/or bottom surfaces shown in the figures) of a substrate 710 (e.g., a silicon wafer optionally having an SiO2