Battery cell and battery

The invention discloses a battery cell and a battery, the battery cell comprises a positive plate, a negative plate and a diaphragm, the positive plate, the negative plate and the diaphragm are mutually stacked, the battery cell is formed by winding the positive plate, the diaphragm and the negative plate, and the positive plate, the negative plate and the diaphragm form a plurality of pole piece rings in the radial direction; wherein each of the positive plate and the negative plate comprises a pole piece main body, an empty foil region and a plurality of tabs, the empty foil region is arranged on one side of the pole piece main body in the height direction, and the tabs are arranged on one side, deviating from the pole piece main body, of the empty foil region at intervals. The pole lug ring of the pole piece ring of the outer circle covers the pole lug ring of the pole piece ring of the inner circle, each circle of pole lug forms a relatively complete plane after being flattened, so that a flat pole lug surface is formed, pores caused by pole lug stacking or non-uniform pole lug thickness do not exist in the pole lug surface, and the welding yield of the pole lug and the collector plate is improved.