1 Seawater Battery SWB explanation Seawater Battery (SWB) A seawater secondary battery uses seawater as an active material or electrolyte, and is an energy storage system capable of charging and discharging. By utilizing natural seawater, the system has the advantages of lower cathode manufacturing costs, abundant raw materials and high fire stability compared to conventional lithium-ion batteries. And in the case of seawater is used as a cathode, sodium ions can be supplied infinitely from natural seawater, so it is a new concept next-generation secondary battery technology with a high theoretical energy density. SWB core technology Na+ selective solid electrolyte Solid electrolyte of SWB locates between seawater and anode to transfer Na+ ions selectively, also simultaneously serves as a that protects the non-aqueous anode from the aqueous cathode. Currently, NASICON (Na Super Ionic Conductor) oxide solid electrolyte, which performs high water resistance and chemical stability, has adopted for SWB, and various shapes of solid electrolytes have been manufactured and applied according to the type of SWB. Stable Na storage anode The anode stores the Na from seawater, and is a part that determines the amount of energy and cycle life of a seawater battery. Because the cell structure of existing sodium-ion batteries and seawater batteries are different, the seawater battery anode is being researched as an energy storage method in its own unique way. Sufficient Na supplement cathode Since natural seawater is used as a catholyte, energy can be stored and used through an electrochemical reaction between salt (NaCl) and water (H2O) dissolved in seawater. Besides seawater, SWBs can also operate in sodium-containing solutions such as salt water, and sodium hydroxide (NaOH). Therefore SWBs have high energy density due to the catholyte supplying a rich Na supply. Seawater battery cell & module SWB cell is developed by combining cathode, anode, and solid electrolyte. We design optimized cells by considering factors that determine cell performance, such as capacity and coulomb efficiency. We also research on SWB module that can be used as an actual energy storage system.
