The invention provides a negative pole piece. The negative pole piece comprises a negative current collector, a negative pole material layer and a niobium-titanium oxide layer which are arranged in alaminated manner, wherein the negative pole material layer is arranged between the negative current collector and the niobium-titanium oxide layer, the niobium-titanium oxide layer contains niobium-titanium oxide, and the mass percentage of the niobium-titanium oxide in the niobium-titanium oxide layer ranges between 70% and 90%. The invention further provides an electrochemical battery.