A three-dimensional solid-state interpenetrating electrochemical cell was synthesized by infiltrating a V2O5 cathode ambigel into a macroporous, polymer-coated carbon anode. The cathode material was characterized using scanning electron microscopy, N-2 sorption analysis, and X-ray photoelectron spectroscopy to determine the overall filling, surface area, and oxidation state of the vanadia material. The lithiated cell was electrochemically cycled. In comparison to a similar, previously prepared cell that employed a V2O5 xerogel cathode, the increased surface area and pore filling of the V2O5 ambigel cathode in this cell generated a significant increase in the reversible gravimetric cell capacity. (c) 2007 The Electrochemical Society.