Excellent electrochemical behavior of LiMn₂O₄ in aqueous electrolyte

LiMn₂O₄ was prepared by a solid-state reaction, and for the first time its electrochemical behavior in the organic and aqueous electrolytes were compared. Since the host structure is the same, the intercalation and deintercalation behavior does not change, and the diffusion coefficient of Li⁺ ions are in the same range. However, due to much higher ionic conductivity of the aqueous electrolyte, its reversible redox behavior at high scan rate is much better than in the organic electrolyte. The reversible capacity in the aqueous electrolyte is 85 mAh · g^-1 at the current density of 50 mA · g^-1, and 22 mAh · g^-1 (26% of the normal capacity) when the current density is up to 10,000 mA · g^-1 (118 C). This shows that aqueous rechargeable lithium battery (ARLB) have very high-power density or excellent rate capability, and good cycling behavior.