Negative electrode material for non-aqueous liquid electrolyte secondary

Abstract

A negative electrode material for a secondary cell for anon-aqueous liquid electrolyte for realizing a high charging/discharging capacity and a high discharging efficiency, a method for producing such material and a non-aqueous liquid electrolyte secondary cell employing such material. The negative electrode material contains at least one carbonaceous material selected from the group consisting of coffee beans, tea leaves, cane sugar, corns, fruits, straws of cereals and husks of cereals, a carbonaceous material derived from a plant-origin high molecular material containing a sum total of 0.2 to 20 wt % of metal elements, phosphorus and sulphur calculated as elements or a carbonaceous material having a diffraction peak between 30.degree. and 32.degree. of the 2.theta. diffraction angle in the X-ray (CuK.alpha.) powder diffraction pattern. For producing the negative electrode material, at least one carbonaceous material selected from the group consisting of coffee beans, tea leaves, cane sugar, corns, fruits, straws of cereals and husks of cereals, or crystalline or fibrous cellulose admixed with at least one of metal elements, phosphorus or sulphur, is sintered for carbonization. The negative electrode material is used for a non-aqueous liquid electrolyte secondary cell having a positive electrode formed of a lithium compound oxide and a negative electrode formed of a carbonaceous negative electrode material capable of doping and dedoping lithium ions as an active negative electrode material.