Alkali metal ion battery with bimetallic electrode

A method of operating an electrochemical cell using electrical energy transferred from an external circuit, the method comprising:

• providing at least one electrochemical cell configured to connect with the external circuit, the at least one electrochemical cell comprising:
• a positive electrode comprising a first liquid phase comprising lead and antimony;
• a second liquid phase defining an electrolyte comprising a halide salt of an active alkali metal and defining a first interface and a second interface, the positive electrode being in contact with the second liquid phase at the first interface;
• and
• a third liquid phase separated from the first liquid phase and defining a negative electrode comprising the active alkali metal in atomic form, the third liquid phase in contact with the second liquid phase at the second interface, the second liquid phase allowing cations of the active alkali metal 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, wherein the first liquid phase is liquid at a temperature below 500° C.;
• electrically connecting the external circuit to a negative pole and a positive pole of the electrochemical cell;
• and
• operating the external circuit so as to produce or receive electrical energy in the electrochemical cell by driving transfer of the active alkali metal to or from the first liquid phase, through the second liquid phase, and to or from the third liquid phase, so that
• in a discharged state of the cell, the positive electrode comprises the active alkali metal in atomic form and the antimony and lead in a certain amount;
• and
• in a charged state of the cell, the positive electrode comprises the antimony and lead in unchanged amounts compared to the discharged state of the cell and a loss of atoms of the active alkali metal.