The invention discloses a battery cell, a battery module and a battery pack, and relates to the technical field of battery cells. The battery cell comprises a shell, a roll core and an electrolyte, the roll core and the electrolyte are arranged in the shell, and the roll core is formed by laminating or winding a positive plate, an isolating membrane and a negative plate which are arranged in a laminated manner; the positive plate comprises a positive current collector and a nickel-containing positive active material coated on the positive current collector, the positive current collector is a composite current collector comprising an insulating support layer and a conductive layer at least arranged on one side of the insulating support layer, the thickness of the insulating support layer is A, the unit is [mu] m, the weight percentage of a nickel element in the positive active material is I, and the unit is [mu] m. The unit is%; the thickness of the isolating membrane is F, and the unit is mu m; and the thickness A of the insulating support layer, the weight percentage I of the nickel element in the positive electrode active material and the thickness F of the isolating membrane satisfy 0.01 < = (A * F/I)/1000 < = 3. The battery cell has the advantages of high energy density and high safety performance.