An electrochemical cell includes a negative electrode having at least two active metals, a positive electrode having a metal or alloy, and an electrolyte having a cation of each of the active metals. The electrolyte defines first and second interfaces with the positive electrode being in contact with the first interface and the negative electrode being in contact with the second interface. The electrolyte is configured to allow the cations of the active metals to be transferred from the negative electrode to the positive electrode during discharging and to be transferred from the positive electrode to the negative electrode during charging. The electrolyte exists as a liquid phase and the negative electrode and the positive electrode exist as liquid or partially liquid phases at operating temperatures of the electrochemical cell.