System and methods of using a sodium metal halide cell

1. A method for operating an energy storage device, comprising:

setting a vertical temperature gradient along an axis of a cell of an energy storage device to apply an idling axial temperature gradient, wherein the vertical temperature gradient is present when the energy storage device is in an idle state; and

charging and/or discharging the energy storage device.

2. The method of claim 1 , comprising charging the energy storage device and maintaining a charging axial temperature gradient across the cell of the energy storage device.

3. The method of claim 2 , wherein the charging axial temperature gradient is different than the idling axial temperature gradient.

4. The method of claim 1 , wherein the idling axial temperature gradient is greater than or equal to 10° C., in a direction along the axis of the cell, from one end of the cell to the other end of the cell.

5. The method of claim 4 , wherein the idling axial temperature gradient is greater than or equal to 20° C.

6. The method of claim 5 , wherein the idling axial temperature gradient is 20° C. to 100° C.

7. The method of claim 1 , comprising discharging the energy storage device and further comprising changing the idling axial temperature gradient during discharge.

8. The method of claim 1 , wherein the energy storage device comprises a sodium anode.

9. The method of claim 1 , wherein the energy storage device comprises a nickel cathode.

10. The method of claim 9 , wherein the cathode of the energy storage device further comprises sodium chloride.

11. The method of claim 1 , wherein the energy storage device comprises an alkali metal ion conductor solid electrolyte as a separator.

12. The method of claim 11 , wherein the solid electrolyte comprises beta″-alumina.

13. The method of claim 1 , wherein the energy storage device is a sodium metal halide battery that comprises a beta″-alumina solid electrolyte.

14. A method for operating an energy storage device, comprising:

setting a first temperature at a bottom end and a second temperature at a top end of a cell of an energy storage device with a temperature management device to apply an idling axial temperature gradient, wherein the second temperature is higher than the first temperature; and

charging and/or discharging the energy storage device.

15. The method of claim 14 , comprising charging the energy storage device and enhancing a charging axial temperature gradient across the cell of the energy storage device, and wherein the charging axial temperature gradient is different than the idling axial temperature gradient.

16. The method of claim 14 , comprising discharging the energy storage device and enhancing a discharging axial temperature gradient across the cell of the energy storage device, and wherein the discharging axial temperature gradient is different than the idling axial temperature gradient.

17. The method of claim 14 , wherein the idling axial temperature gradient is greater than or equal to 20° C.

18. The method of claim 17 , wherein the idling axial temperature gradient is greater than or equal to 40° C.

19. An energy storage system, comprising:

an energy storage device comprising:

a housing having an axis and an interior surface defining a volume;

a separator disposed in the volume and having a first surface that defines at least a portion of a first chamber and a second surface that defines at least a portion of a second chamber, wherein the first chamber is in ionic communication with the second chamber through the separator;

a cathodic material in ionic communication with the separator; and

an electrolyte in ionic communication with the cathodic material and the separator; and

a temperature management device comprising a controller, wherein the temperature management device is configured for setting and controlling a vertical temperature gradient along the axis when the energy storage device is in an idle state.

20. The energy storage system of claim 19 , wherein the temperature management device is configured for setting a first temperature at a bottom end and a second temperature at a top end of the energy storage device, wherein the second temperature is higher than the first temperature.