An anode subassembly for use in an implantable electrochemical cell includes a solid anode current collector and an alkali metal anode pressed onto the solid anode current collector such that the solid anode current collector is located on the outer side of the outermost winding of a coiled electrode assembly formed when the anode subassembly is wound with a cathode subassembly. The anode subassembly may further include a spacer formed from a microporous, non-conductive material pressed onto the alkali metal anode on the opposite side from the solid anode current collector.