A hand-held, electrically powered and controlled surgical stapler/cutter includes a handle shaped to fit in one hand of a user and a surgical end effector connected to the handle. The handle contains therein a selectively actuated, self-contained electric power supply having at least one battery cell, at least part of an anvil control assembly, and at least part of an electrically-powered stapler/cutter control assembly electrically connected to the power supply. The surgical end effector is operatively connected to each of the anvil control assembly and the stapler/cutter control assembly. The stapler/cutter control assembly staples and cuts tissue disposed at the surgical end effector when powered by the power supply.