An anode for an energy storage device includes a current collector having an electrically conductive layer that includes nickel or copper, and a lithium storage structure comprising a plurality of first microstructures in contact with the electrically conductive layer. Each first microstructure includes silicon and is characterized by a first maximum width measured across the widest section orthogonal to the first microstructure axis. Each first microstructure includes a first portion characterized by the width substantially tapering from the maximum width to a location where each first microstructure contacts the electrically conductive layer and a second portion positioned farther from the electrically conductive layer than the first portion, the second portion defining a substantially hemispherical shape and the top of each first microstructure. The lithium storage structure has at least 1 mg/cm2 of active silicon and a total atomic % of nickel and copper is from 0.5% to 1.2%.