The viability of cheaper sodium-ion batteries in an energy storage system at the grid level has been proven by the first utility station that is now operational.
The low cost of the sodium cells can lead to electricity generation at a price of less than $0.03 per kWh, and this is one of the greatest advantages of sodium-ion battery packs.
Located in Guangxi, the 10 MWh sodium battery station uses 210 Ah cells that can be charged to 90% in just 12 minutes.
In them, instead of using the more expensive lithium for the cathode, the battery manufacturers employs cheap and abundant sodium.
The energy density is still not up there with the lithium-ion chemistry, so for now sodium batteries only go into compact EVs, but for energy storage applications they can be a good alternative to LFP power stations.
The first grid-scale energy storage system built with sodium-ion batteries consists of 22,000 cells whose thermal management solution keeps their core temperature within 3 degrees Celsius from each other.
In the case of thermal runaway, the spreading event will now take 2 hours instead of half an hour, report the engineers of the China Southern Power Grid utility that has built the system.
There are a number of such sodium-ion battery energy storage projects in the making, but the presence of an actually operational station as part of an official utility mix gives credence to the commercial viability of sodium batteries.
