▎ 摘　　要

NOVELTY - An aluminum-ion secondary battery comprises a positive electrode, a negative electrode, an electrolyte and a separator. The positive and negative electrodes are connected to the separator. The positive electrode is a composite sheet of graphene and nickel-titanium alloy. The negative electrode is high-pure aluminum. The electrolyte comprises trivalent aluminum ion, chloride ion and 1-ethyl-3-methylimidazolium ion. The molar ratio of 1-ethyl-3-methylimidazolium ion and trivalent aluminum ion is more than 3: 2 to less than 4:1. USE - Aluminum-ion secondary battery (claimed). ADVANTAGE - The aluminum-ion secondary battery has excellent thermal stability and cycle rate of more than 5000 times, energy density of 90 Wh/Kg or more and charge and discharge rate of 3.5 V or more. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of aluminum-ion secondary battery.