A rechargeable aqueous lithium ion battery containing all-NASICON type cathode and anode materials is proposed and developed for the first time. In the design, LiTi2(PO4)3 and Li3V2(PO4)3 serve as the anode and cathode, respectively, which can fulfill the electrochemical window of aqueous solutions and ensure fast lithium ion diffusion into/from electrodes thus provide a safe, fast, inexpensive aqueous lithium ion battery. However, the capacity fading of the Li3V2(PO4)3 is extremely serious in common aqueous solutions. Therefore, the fading mechanism is systematically investigated and “water in salt” aqueous electrolyte is introduced to further solve the fading problem. Consequently, the cycling stability is greatly improved. Even after 100 cycles at 0.1 C, there remains a high reversible capacity of 104 mAh g−1, which is 83.2% of the initial discharge capacity. Furthermore, benefiting from the all-NASICON electrodes construction and super low freezing point of “water in salt” electrolyte, the aqueous battery deliveries remarkable low-temperature performance. It is a powerful and safe candidate for extreme-situation energy storage applications.