About NAS Batteries
- Molten sodium donates electrons to the external circuit at the anode
- The resulting ions Na+ migrate to the cathode through the beta-alumina solid electrolyte that separates the two liquid electrodes and that acts as a superionic conductors
- The volume of liquid at the anode therefore decreases
- Arriving at the cathode, Na+ ions combines with molten sulfur which reacts with the electrons coming from the external circuit, forming sodium polysulfide Na2Sx
- The volume of liquid at the cathode therefore increases
2 Na + x S → Na2Sx with 3.3 ≤ x ≤ 5
- The reverse process takes place
|Energy density||367 Wh/l
|Power density||36 W/kg|
|C-rate||1 / 6 = 0.17|
|Optimal temperature range||300 - 340°C|
|Maximal temperature range||290 - 360°C|
|Life time||4500 cycles
Features of NAS Batteries
NGK's NAS batteries are large-capacity batteries with many power grid applications.
Superior function and performance possible only from decades of research, design, testing, demonstration, advanced manufacturing and over 15 years of proven commercial operation.
Major Advantages of NAS over other battery technologies
NAS battery is a large-capacity, long-duration storage battery suitable for daily load leveling and time shifting of wind and solar generation.
Long life expectancy
NAS battery has a calendar life of 15 years and a full charge/discharge durability of 4500 cycles.Since the active materials of the NAS battery are in molten states, there are no transition between solid and liquid due to charge and discharge, and there is no side reaction, so long life can be expected.
Tolerance for cold and high temperature environment
NAS battery, which operates at 300-340 degree C. in a thermal enclosure, satisfies optimal operating conditions without air conditioning in cold and hot areas.
NAS and the NAS logo are trademarks of NGK INSULATORS, LTD., registered in the U.S. and other countries.