Thetestingsuccessfullydemonstratedagrid-connected,highvoltage(>1,000 V), 13. 5 kWh system with a 4-hour discharge time. A sodium-ion battery (NIB, SIB, or Na-ion battery) is a rechargeable battery that uses sodium ions (Na +) as charge carriers. 5°C Scenario requires global battery storage capacity to increase from 17 GW in 2020 to 360 GW in 2030 and 4 100 GW in 2050 to provide the flexibility needed for a power system based on renewable electricity, as shown in Table 1.