Water system chargeable sodium-ion battery

The invention discloses a water system chargeable sodium-ion battery system. The system uses a concept of a 'rocking chair battery' of a lithium ion battery; and the entire battery system is formed by using sodium-based prussian blue matter as an embedded anode, titanium sodium phosphate as an embedded cathode, and sodium-contained inorganic salt solution as electrolyte. The system has the advantages of high discharge voltage, large specific capacity, good rate capability, long cycle life and the like, and further has the characteristics of green and environmental friendliness, and high security and no pollution. The system very hopefully becomes an electrochemical stored energy system with low price and environmental friendliness.