An Ultralong Lifespan and Low-Temperature Workable Sodium-Ion Full Battery for Stationary Energy Storage

Presently, commercialization of sodium-ion batteries (SIBs) is still hindered by the relatively poor energy-storage performance. In addition, low-temperature (low-T) Na storage is another principal concern for the wide application of SIBs. Unfortunately, the Na-transfer kinetics is extremely sluggish at low-T, as a result, there are few reports on low-T SIBs. Here, an advanced low-T sodium-ion full battery (SIFB) assembled by an anode of 3D Se/graphene composite and a high-voltage cathode (Na3V2(PO4)(2)O2F) is developed, exhibiting ultralong lifespan (over even 15 000 cycles, the capacity retention is still up to 86.3% at 1 A g(-1)), outstanding low-T energy storage performance (e.g., all values of capacity retention are >75% after 1000 cycles at temperatures from 25 to -25 degrees C at 0.4 A g(-1)), and high-energy/power properties. Such ultralong lifespan signifies that the developed sodium-ion full battery can be used for longer than 60 years, if batteries charge/discharge once a day and 80% capacity retention is the standard of battery life. As a result, the present study not only promotes the practicability and commercialization of SIBs but also points out the new developing directions of next-generation energy storage for wider range applications.