Abstract: A lithium-ion battery with medium and small capacity and high output, comprises a shell, a cell core and electrolyte located in the shell; the said cell core obtained by winding anode sheets, cathode sheets and separators between the anode sheets and cathode sheets, the said anode sheets coated with anode active material, the said cathode sheets coated with cathode active material; the said anode active material includes LiMn2O4, especially still includes LiCoO2 and/or LiNiCoO2; the conductivity of the said electrolyte is 11-20 ms/cm; the length of the said anode sheets and cathode sheets is 700-2400 mm, and the thickness is 65-135 ?m.