An electrochemical cell is described. The electrochemical cell includes an anode, a cathode, a separator between said anode and said cathode, and an electrolyte. The electrolyte includes a salt dissolved in an organic solvent. The separator in combination with the electrolyte has an area specific resistance less than 2 ohm-cm2. The electrochemical cell has an interfacial anode to cathode ratio of less than about 1.1.