whereby the discharge capacity decreases here if a polyamic acid alone is used for the binder it becomes sometimes difficult in the operation of applying a slurry comprising the binder to the substrate to achieve uniform application resulting in occurrence of non uniform reaction however since in the present invention a polyamic acid is used as a binder in the form of a mixture of itself with at least one polymer selected from the group consisting of a polyamide resin polyvinylpyrrolidone and a hydroxyalkylcellulose the slurry of the mixed binder solution with graphite dispersed therein can be uniformly applied to the substrate so that the reaction of the negative electrode active material can be effected uniformly throughout the electrode surface in addition since in the present invention the mixed binder used contains no fluorine there is no danger associated with conventional lithium secondary batteries that the hydrogen fluoride formed by thermal decomposition of the binder used could vigorously react with c 6 li to cause the battery to break or burst other features of the invention will become apparent in the course of the following descriptions of exemplary embodiments which are given for illustration of the invention and are not intended to be limiting thereof a slurry for positive electrode was prepared by mixing 90 parts by weight of licoo 2 as a positive electrode active material 6 parts by weight of graphite as a conductive agent and as a binder 4 parts by weight of polyvinylidene fluoride that had been dissolved in n methyl.