The invention provides an electrical core structure for a lithium ion power battery, comprising a positive plate, a positive electrode ear, a barrier membrane, a negative plate and a negative electrode ear, wherein the positive plate is formed by evenly coating positive active substances on two surfaces of an aluminum foil, the negative plate is formed by evenly coating negative active substances on two surfaces of a copper foil, the positive plate has a shape of a convex single electrode ear, the barrier membrane is formed by overlapping a double-layer barrier membrane through welding to form a structure which has an opening in one direction and has a shape similar to a paper bag, a plurality of positive plates are respectively arranged inside the barrier membrane bag, the negative plate is folded reciprocally according to the shape of Z, the positive plate is inserted into the two adjacent layers of the negative plates, and the positive plate, the barrier membrane and the negative plate form an electrode aggregate with a semi-overlaying structure. The electrical core structure has the advantages of solving the problems that the negative electrode in the electrical core can not completely wrap the positive electrode and the barrier membrane in the winding of a long electrode plate is overlong and can not correspond orderly, improving the problem of the internal short circuit caused by contractive and deformed barrier membrane, and improving the safe stability of the use of the battery.