To provide high battery capacity by further improving energy density in a lithium secondary battery improved in a charging discharging cycle characteristic by using a mixture of natural graphite with coke and/or hard carbon for a negative electrode active material and a lithium-containing nickel-cobalt composite oxide for a positive electrode active material.
This lithium secondary battery is provided with a negative electrode 2 containing a mixture of natural graphite with coke and/or hard carbon as a negative electrode active material, a positive electrode 1 containing a lithium-containing nickel-cobalt composite oxide expressed by LiNixCo1-xO2 (0.4<X<0.9) as a positive electrode active material, and a nonaqueous electrolyte. In this case, polyvinylidene fluoride having a weight average molecular weight of 500,000 or more is used for a binder of the positive electrode 1, and the ratio of the binder contained in the positive electrode 1 is set in the range of 1.0-2.1 wt.%.
YANAGIDA KATSUISA
MAEDA TAKESHI
FUNABASHI ATSUHIRO
NOMA TOSHIYUKI
YONEZU IKURO
