| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a non-aqueous electrolyte secondary battery which exhibits a superior cycle characteristic, and to provide its manufacturing method. <P>SOLUTION: Disclosed is a non-aqueous electrolyte secondary battery having a negative electrode which uses silicon as an active material, and employing a non-aqueous solvent which includes a fluorine-containing solvent. This battery is configured so that with respect to silicon contained in a negative electrode active material layer removed from the battery, the amount ratio of fluorine contained in the active material layer is 5 to 30% by weight after at least 100 cycles of charging/discharging 50% or more of the battery capacity. The method for preferably manufacturing the battery includes the steps of, on a film coating formed by means of coating a collector with a particle consisting of silicon as an active material, performing electrolytic plating using a plating bath more than pH7, thereby depositing copper on the surface of the particle; acid washing so as to manufacture a negative electrode; assembling the non-aqueous electrolyte secondary battery using the negative electrode along with a positive electrode, a separator, and a non-aqueous solvent which includes a fluorine-containing solvent; and performing first-charging of the assembled battery with low rate of 0.005 to 0.03C. <P>COPYRIGHT: (C)2009,JPO&INPIT |
