A method includes, by a folding station: receiving an anode assembly including anode collectors connected by anode interconnects and coated with a separator; receiving a cathode assembly including cathode collectors connected by cathode interconnects; locating a first anode collector over a folding stage; locating a first cathode collector over the first anode collector to form a first battery cell between the first anode collector and the first cathode collector; folding a first anode interconnect to locate a second anode collector over the first cathode collector to form a second battery cell between the first cathode collector and the second anode collector; folding a first cathode interconnect to locate a second cathode collector over the second anode collector to form a third battery cell between the second anode collector and the second cathode collector; wetting the separator with solvated ions; and loading the anode and cathode assemblies into a battery housing.