Core technology

Blue battery technology

What is blue battery?

‘Blue battery’ is the high-capacity and long-duration energy storage system using seawater that ensures stable supply and is safe for fire. In short, it is the seawater based energy (blue energy) storage system.

The principle of blue battery

The Blue Battery applies the principle of separating the ions (N+ and Cl-) in seawater to store energy. During charging, it ion-separates the salt in seawater. At this time, the catholyte becomes an alkaline solution with a pH of 10-11, and the anolyte becomes an acidic solution with a pH of 3-4. During discharging, it obtains electrical energy through the acid-base reaction. In the case of acid-base reaction based energy storage, its theoretical energy density is relatively lower than that of conventional energy storage technology. Nevertheless, it is economic because energy is stored in seawater.


Energy storage through the separation of seawater into acid and base

(energy storage density : 5~7Wh/L)


energy production through the conversion of acid-base reaction into electric energy (output density : 20~30W/㎡)

Why is blue battery needed?

ESS for renewable energy storage mainly applies the method of storing energy in natural objects to reduce operation cost (i.e., water, air). Since blue battery utilizes seawater, it has inexpensive levelized cost of storage. Once commercialized, it is expected to cost at about 0.1~0.2 dollars per 1kWh. The cost of the storage technology is similar to that of pumped-storage hydroelectricity which is known to be the most economic so far. Its energy density is higher.

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