Sodium ion based aqueous electrolyte electrochemical secondary energy storage device

摘要

A secondary hybrid aqueous energy storage device includes an anode electrode, a cathode electrode which is capable of reversibly intercalating sodium cations, a separator, and a sodium cation containing aqueous electrolyte, wherein an initial active cathode electrode material comprises an alkali metal containing active cathode electrode material which deintercalates alkali metal ions during initial charging of the device.

主权项

1. A method of operating a hybrid aqueous energy storage device comprising an anode electrode, a cathode electrode, a separator, and a sodium containing aqueous electrolyte, the method comprising:
providing the storage device in which the cathode electrode comprises an active cathode electrode material comprising lithium manganate cubic spinel material having a formula LixMn2-zAlzO4 where 1≦x<1.1 and 0≦z<0.1; deintercalating lithium ions from the active cathode electrode material during initial charging of the device to form a substantially lithium free cubic spinel λ-manganate active cathode electrode material; reversibly intercalating sodium ions from the electrolyte into the active cathode electrode material during a subsequent discharge cycle to form a cubic spinel λ-manganate active cathode electrode material having a formula AyMn2-zAlzO4 where A comprises at least 80 atomic percent Na, 0≦y<1, and 0≦z<0.1; and reversibly deintercalating sodium ions from the active cathode electrode into the electrolyte during a subsequent charge cycle.