Anodes for lithium-based energy storage devices

An anode for an energy storage device, the anode comprising:

• a current collector comprising an electrically conductive layer;
• and
• a lithium storage structure comprising a plurality of first microstructures in contact with the electrically conductive layer,
• wherein:
• (i) each first microstructure comprises silicon,
• each first microstructure is characterized by a first maximum width measured across the widest section orthogonal to a first microstructure axis,
• each first microstructure comprises a first portion, the 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
• each first microstructure comprises a second portion, the second portion positioned farther away from the electrically conductive layer than the first portion is from the electrically conductive layer, the second portion defining a substantially hemispherical shape and the top of each first microstructure,
• (ii) the electrically conductive layer comprises nickel or copper,
• (iii) the lithium storage structure comprises at least 1 mg/cm2 of active silicon, and
• (iv) a portion of the lithium storage structure comprising the surface of the lithium storage structure comprises a total atomic % of nickel and copper in a range from 0.05% to 1.2%.