Negative electrode piece and secondary battery including same

A negative electrode piece, comprising a negative-electrode current collector and a negative-electrode active material layer coated on one or both surfaces of the negative-electrode current collector, the negative-electrode active material layer comprising a negative-electrode active material, a conductive agent and a polymer, wherein the polymer comprises a repeating unit as shown in Formula 1 below:

• in Formula 1, R1 is selected from H or C1-6 alkyl group;
• R2 is selected from a connecting group;
• R3 is selected from a capping group;
• M is a polyphenylene oxide chain segment;
• and
• the polyphenylene oxide chain segment has a repeating unit shown in Formula 2:
• in Formula 2, R4 is selected from H or C1-3 alkyl group, and m is an integer between 0-2,
• wherein R2 is a connecting group formed by a reaction of hydroxyl group in
• with R3′ in
• R3 and R3′ are same or different, and are each independently selected from H, OH, COOH and NH2 and are not H at the same time.