In a non-aqueous electrolyte secondary battery having a negative electrode
containing Si as a negative electrode active material, a binder
containing a non-crosslinked polyacrylic acid having a weight-average
molecular weight of 300,000 to 3,000,000 is incorporated into a negative
electrode molded article that constitutes the negative electrode, so as
to prevent electrode decay resulting from expansion and contraction
during charge/discharge, as well as to achieve high energy density and
improved charge/discharge cycle characteristics.