NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY AND METHOD FOR MANUFACTURING THE SAME

• Main Authors: NONAKA TAIKI, NOHMA TOSHIYUKI, MINAMI KEISUKE, YAMAUCHI YASUHIRO, FUJIHARA TOYOKI
• Format: Patent
• Language: English; Korean
• Published: 30.08.2011
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

An aspect of the invention provides a nonaqueous electrolyte secondary battery including a flattened electrode assembly in which a positive electrode plate containing lithium transition metal composite oxide as positive electrode active material, and a negative electrode plate containing carbon material able to insert and extract lithium ions as negative electrode active material, are stacked and wound with a separator interposed therebetween, and a protective layer constituted of inorganic oxide and an insulative binding agent provided on a surface of the negative electrode plate. The arithmetic mean surface roughness Ra of a face of the separator that contacts with the protective layer is 0.40 to 3.50 μm. With the invention, a nonaqueous electrolyte secondary battery is obtained that has enhanced formability of the flattened electrode assembly and superior output characteristics and other battery characteristics.