▎ 摘　　要

NOVELTY - An electrolyte comprises lithium salt and organic solvent. The lithium salt comprises at least two lithium halides comprising lithium iodide, organic lithium salt, and other one or more inorganic lithium salt. The organic solvent comprises urea compound. The molar ratio of lithium iodide to other lithium halide in the electrolyte is 0.1-1.5:0.1-1.5. The concentration of lithium iodide in the electrolyte is 0.1-1.5 mol/L. USE - Electrolyte used for lithium-ion battery (claimed) as energy storage device used in digital product, energy automobile and energy storage application. ADVANTAGE - The electrolyte has excellent cycle durability, and increases the solubility of lithium salt, and effectively increase the battery capacity. On the basis of positive electrode sheet with high carbon content, lithium-ion battery with higher discharge capacity, energy density and cycle stability can be obtained. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for lithium ion battery, which comprises electrolyte and positive electrode sheet. The positive electrode sheet comprises type (A) of conductive agent and type (B) of conductive agent. The type (A) of conductive agent is porous activated carbon with specific surface area of 3000-3500 m2/g, pore volume of 1-2 ml/g, and average pore diameter of less than 2 nm. The type (B) of conductive agent is at least one of acetylene black, Ketjen black(RTM: electro-conductive carbon black), single-walled carbon nanotube, multi-walled carbon nanotube, conductive graphite or graphene.